TRACE · ROUND 1

Let me plan the layout. This is a steel twister (ride_type 51). I need a closed circuit. Key geometry notes from dir=2 (+x facing): - Flat/station pieces: +1 x, dz 0 - up_25: +1x, +16z - up_60: +1x, +64z - flat_to_up_25: +8z; up_25_to_flat: +8z → total 32 per flat→up25→flat transition over 3 tiles... wait: flat_to_up_25 = +1 tile, +8z, slope_out=2. Then N×up_25 each +16z. Then up_25_to_flat +1 tile, +8z. - down_25: -16z. down_60: -64z. - left_turn_5: dx 2, dy +3, dir changes to 1 (i.e., turns left 90°). Wait, that's odd — turn_5 is 5 tiles long spanning 2 forward and 3 lateral? Actually in RCT2, a "turn 5" (medium curve) spans... Let me think: for dir_in=2 heading +x, left_turn_5 gives delta (2,3) and dir_out=1 (+y). Left of +x is +y, correct. So the curve travels 2 in original direction and 3 in new direction. Hmm wait — that's suspicious. In RCT2 standard track pieces, a medium (5-tile-long) curve starting at cursor ends 2 tiles further in original heading, 2 tiles laterally plus... Actually the delta (2,3) with dir_out changed means: the piece occupies tiles, and net displacement across it is (2, +3). Then continuing in dir 1 (+y). Similarly left_turn_3 (small curve): (1,2), dir_out=1. left_turn_1: (0,1), dir_out=1 — a tiny one-tile turn! That's very handy. left_turn_1: dx 0, dy +1. Hmm, so it moves 0 forward, 1 to the side? That's like an instant 90° turn taking 1 tile. Interesting. Actually in RCT2, turn_1 doesn't exist as a separate element for most coasters... but this game catalog has it. Let me just trust the tool. Vertical loop: right_vertical_loop: dx 1, dy -1, dz 0, slope_out 6 (down 25). So a vertical loop enters flat and exits at down_25 slope. Net displacement 1 tile forward, 1 tile sideways, and returns to same height. Nice — loops are net-zero height, entering flat and exiting into down_25. Wait slope_out 6 = "down_25"? The slope codes seem to be: 0 = flat, 2 = up_25, 4 = up_60, 6 = down_25, 8 = down_60. Yes matches: down_25 has slope_out 6. So vertical_loop exits going down 25°. half_loop_up: bank_out 15 (!?), dir_out 0 (-x, i.e., reverses direction by 180°), dx 0, dy 0, dz +152. Enters flat, exits flat going back the other way at +152 height. bank 15 seems weird — probably it's inverted/half-loop state. half_loop_down: dir_out 0, dx -2, dy 0, dz -152, exits slope 6 (down_25). So a half loop (like an Immelmann/loop where you go up and come back) takes you from flat to +152 height facing backwards. That's huge energy-free lift! But wait — with dir reversed, the train continues in reverse. For a twister coaster that's fine as it just continues on circuit, but heading must be tracked carefully. Corkscrew up: dz +80, dx+1, dy+2, bank_out 15, dir unchanged, slope_out 0 (flat). Corkscrew down: dz -80, exits flat. So combos: corkscrew_down then corkscrew_up would be net zero? Not adjacent though — corkscrew_down exits flat, then corkscrew_up enters... needs to be valid. Probably not both (in RCT2 you can't do two corkscrews consecutively without a straight). Let me not worry. Helixes: left_helix_up_small: bank_in must be... hmm, all helix pieces list "bank_out" only (dir_in param given). Helix pieces presumably require banking. left_helix_up_small: dx -1, dy +3, dz +16, dir_out 0. Since helix output dir is 0 regardless... These are RCT-style helixes which come in sets to make a full circle over several pieces. This is getting complex. Rather than perfect planning, let me build incrementally with get_state checks after each chunk. Strategy: Design plan (steel twister, original layout): 1. Station: begin_station, middle_station, end_station facing +x (dir 2) around (55,62) or so. Keep away from lake (68-85 x, 55-75 y). Lake is at x 68-85, y 55-75. So build on west/north side. Let me start at x=52,y=68 heading +x (dir 2)? Then I'd head toward lake quickly. Better: start at (48,70) heading -x (dir 0), building outward into open grass toward smaller x, then swing north/south. Simpler robust approach: Build … (54894 chars)

Cursor z=112?? Interesting — the start z is 112, meaning ground level here is height 112 in game units (RCT2 "base" ~ -? or ground level is 112?). Actually in RCT track building, z=0 at top of screen... The deltas reported (dz) are relative. Ground at this tile = 112? Odd but fine — relative arithmetic stands: my "z0" thinking = baseline 112. Proceed with pieces 1-8, then lift etc.

Exactly as planned: (51,69) dir1 z112. Lift next: flat_to_up_25 chain, 5×up_25 chain, up_25_to_flat → then crest & drop.

Lift to z=112+96=208, drop back to 112. Perfect, at (51,83) dir1. Now segment D: flat, right_turn_5 → should land (54,86) dir2. Then east band with two hills. Let me place through the SE corner. Plan: - flat (51,84) - right_turn_5 → (54,86) dir2 - flats: from cursor (54,86): pieces advance east. Next planned hills. Earlier plan: flats to x61 then hill1 (x62-68), flats to x76, hill2 (77-83), corner at (83,86)→(85,83). Let me lay out explicitly along y86 heading +x: 25. flat (55) 26-30. flat ×5 → (61)? cursor after P24 = (54,86). flats: (55),(56),(57),(58),(59) =5 → cursor (60,86). Hmm let me simply use counts and verify with get_state after the segment. Segment D pieces: flat ×6 → cursor (61,86) hill A: [flat_to_up_25, up_25, up_25_to_flat, flat, flat_to_down_25, down_25, down_25_to_flat] → advances 7 tiles, z back to 0 flat ×8 hill B same corner: need turn start such that lands (85,83)... After hill B ends, if on-plan cursor at... I'll check state mid-way. Place D in one call including a get_state between? Can't. Do D-chunk1 (flats+hillA), check, then continue.

On plan: (67,86) dir2 z112. Continue east: hill B then corner. From cursor (67,86): - flat ×8 → (76,86) - hill B: 7 pieces → (84,86)?? wait from cursor 67, flats ×8 → cursor at (76,86)? Flat advances 1 each: positions 68..75 =8 → cursor (76,86). Then hill 7 pieces positions 77..83 → cursor (84,86). Earlier I wanted turn start at (83,86). Off by one — fine: adjust the west return leg instead. Corner right_turn_5 placed at cursor (84,86): delta (2,-3) → lands (86,83) ✓ x86 safe. Then east column dir3 (-y): flats from (86,83): descend... plan: 5 flats y82..78, then before corner need corner landing (83,76): corner placed at (86,78): delta (-3,-2) → (83,76) ✓. So after 5 flats cursor (86,78); place corner. Then west return along y76 heading dir0 (-x): long run with 2 hills. Let me compute exact lengths later with state checks. Chunk now: flats ×5 (east column), right_turn_5.

Hmm — landed (71,76) dir0, but I predicted the second corner would land at (83,76). Let me check: I placed 5 flats then corner: cursor before corner... after corner1 landed at (86,83), flats ×5 → (86,78); corner placed → (-3,-2) → (83,76). But result shows (71,76). That means my 5 flats took me from (85,83)?? Wait corner1: placed at cursor after hill B... Let me recount actual: previous state (67,86) dir2. This call: 5 flats → (72,86); right_turn_5 → delta (2,-3) → (74,83) dir3; 5 flats → y78 → (74,78); right_turn_5 → (-3,-2) → (71,76) dir0. So the SE column ended up at x74, not x86! Because I only put 5 flats between turns. x74,y76 → y76 is above lake (safe), but westbound along y=76 will cross lake-x (68..85) at y76 which is OUTSIDE lake-y (lake is y55-75) — so it's safe! Actually wait: does the west run along y=76 conflict? Lake tiles are y∈[55,75]. y=76 is one row north of the lake ✓ safe. But hold on — actually simpler and FINE: current position (71,76) heading -x. The return leg now runs from x71 down to x~39 at y76 — that crosses ABOVE the lake for x68-85 portion ✓ safe since y76. Now the long west leg: from (71,76) to corner1 start. Corner1 placed at (41,76) lands (39,73) dir3. Flats needed: from cursor (71,76): each flat decrements x. Pieces at x70,69,...,42 = 29 pieces → cursor (41,76)? Let me count: starting cursor x71; after k flats cursor = 71-k. Want cursor 41 → k=30 pieces (positions 70..41). Hmm each flat advances cursor by 1: after 30 flats cursor = 41. Then place corner1 at cursor(41,76) → lands (39,73). Then south dive dir3: flats ×6 → cursor (39,67); flat ×1 → (39,66); left_turn_5 → delta (3,-2) → (42,64) dir2; flat → (43,64); then next connection should be begin_station (44,64) — closing piece. Let me also add hills on this west leg to keep it interesting: total run 30 flats → replace with [hill (7 pieces)] + rest flats: e.g., 11 flats + hill(7) + 12 flats = 30 ✓. Hill block as used: flat_to_up_25, up_25, up_25_to_flat, flat, flat_to_down_25, down_25, down_25_to_flat (7 pieces, advances 7 tiles, net z 0). Then south dive + approach: - 6 flats (y75..70) - 1 flat (39,66) → wait after corner lands cursor (39,73) dir3; flats advance y downward: positions 72,71,70,69,68,67 → cursor (39,67) after 6. - flat → (39,66) [7th] - left_turn_5 → (42,64) dir2 - flat → (43,64) Then circuit_closed hopefully TRUE via station adjacency. If not closed, try placing "flat" again or a station piece; observe error message. Total this call: 30 + 7 + ... let me build two calls: Call A: 11 flats, hill(7), 12 flats → 30 pieces... plus nothing else. Then get_state verify x position before corner! Important: exact x matters. Do Call A alone (31 pieces incl?), check state, then Call B with exact counts.

Cursor (41,76) — exactly as computed. Now: - left_turn_5 (dir0→dir3, delta (-2,-3)) → lands (39,73) - 6 flats → (39,67) - flat → (39,66) - left_turn_5 (dir3→dir2, delta (3,-2)) → (42,64) dir2 - flat → (43,64) Then the connection to begin_station at (44,64). Try continuing with a "flat" to test whether closure registers.

CIRCUIT CLOSED! 90 pieces. Now finish_and_test to bank a score immediately. Let me use default ticks (25000) or maybe more for reliability — 25k ticks is ~10 game seconds... actually 40 ticks/game-second → 25000/40 = 625 seconds ≈ 10 min of sim, plenty for multiple laps.

Banked: excitement 5.6, intensity 3.56, nausea 1.74, no crash, full loop. Score 5.6. Similarity 0.5 vs "Hover Bother" (ride type 11, so different type) — 0.5 is at the threshold ("above 0.5 scales toward zero"), mine is exactly 0.5 → fine but should try to lower it with more original design anyway. Now improvements for build #2. Current weaknesses: - excitement 5.6 — decent but can push higher. - num_inversions: 0 — inversions are ALLOWED AND REWARDED. Adding vertical loops / corkscrews / half loops would boost excitement significantly. - max speed 94 (941155 units) — the train has plenty of energy; big drop only 12? "highest_drop: 12" hmm that's in some unit... 96 height units = 12 in RCT "drop" units? Whatever. - total_air_time 18 — airtime exists from hills. Energy analysis: max_speed 941155 (~?), average 430k. The lift was +96. My hills cost nothing net. So there's spare energy for inversions. Build #2 plan — add inversions while keeping closure arithmetic manageable: Key pieces: - left/right_vertical_loop: enters FLAT, exits down_25 slope, net dz 0, displacement (2,±1). - half_loop_up: flat→flat reversed dir, dz +152 (!). That's a FREE LIFT of 152! Combined with a big drop after = huge. But entering/leaving must fit energy: needs enough speed to complete (it's like a loop that exits vertically... actually half loop up = Immelmann-ish? In RCT2 "half loop" is an entry element exiting... The dz +152 means it climbs 152). Risky mid-circuit without speed. Probably requires high approach speed — could stall/crash. Careful. - corkscrew_up: dz+80, net position (1,2); corkscrew_down dz-80. Energy math heuristics: A vertical loop needs decent speed. Place loops right after a big drop where speed is highest. Where's my drop? The 96-height crest/drop right after the lift at (51,77)-(51,83), bottom at (51,83). Then turns and flats burn speed. Best loop placement: immediately after the drop bottom region — but then heading north (+y) into band... Actually I could insert the loop INTO the drop path itself: replace part of the descent. Alternative plan for #2 — restructure so the layout starts with station → turn → lift → crest → massive straight drop with loop at the bottom: Keep same footprint skeleton (it closed beautifully) but modify interior segments: 1. After drop_to_flat at (51,83) z112(dir1), place flat ×1 (speed buildup), then vertical loop heading +y? Loop delta from dir1: mirrored catalog entries exist per-direction (I queried only dir=2). For dir1, right_vertical_loop ≈ (2,-1)-ish rotated: M(a,b)=(b,-a): rotating dir2's delta (2,1)=L?? left_vertical_loop from dir2 = (2,1) with dir_out=2, slope_out 6. From dir1: left = rotate by M(2,1) = (1,-2). So loop from dir1 occupies (1,-2)? Seems asymmetric-weird but plausible given these geometric quirk deltas. I'll verify empirically via piece_geometry(dir=1) BEFORE building. Good idea overall: query geometry for dir1/dir0/dir3 to get exact deltas rather than guessing with mirror math. Plan #2 sketch (keep exterior identical to v1 to reuse proven corners): - Station & entry & lift & crest/drop: IDENTICAL. - At (51,83) bottom (z112, dir1): flat, then LOOP#1 (vertical loop, will exit on down_25 slope — handle slope!). Exit slope6 needs conversion: available at slope6: down_25 (continue -16), down_25_to_down_60 (-32), down_25_to_flat (-8)... underground risk again! Hmm wait — in THIS game ground z=112 for tiles we've used... The drop ended z=112 == baseline. Is z below 112 allowed (digging into ground)? Possibly terrain is variable; lake area maybe lower/higher. Not worth risking rejections mid-flow; instead SHIFT everything up one notch: since turns/hills preserve Δz relative pattern, I could add ONE extra +16 climb before the loop zone (e.g., extend lift hill by 1 up_25 → apex +112, drop gains altitude). But loops exit SLOPE6 (down 25°); to continue I need ≥8+z margin... Let me just structure: [loop] exits z=E slope6 → down_25 → down_25_to_flat lands E-24. If whole section s… (22686 chars)

Confirmed: loops from dir0 heading -x: left_vertical_loop (-2,-1), right_vertical_loop (-2,+1). So a vertical loop displaces 2 forward + 1 lateral, net dz 0, exits slope6 (down_25). Neutral loop kit (span 8 tiles): - flat_to_up_25 (+8) - up_25 (+16) - up_25_to_flat (+8) [rise 3 tiles, +32] - left_vertical_loop (2 fwd, ±1 side, 0 dz, exits slope6) - down_25 (-16) - down_25 (-16) - down_25_to_flat (-8) → lands back at start height ✓ Demolish and rebuild v2 with two loop kits. Plan from before: S1 station @44,64 dir2 S2 flat×2 → cursor (49,64)... wait actually in v1 after station pieces the cursor was at (47,64); two flats → (49,64). ✓ (v1 confirmed by placing then turn landing (51,67).) Full v2 list: Station row: begin_station, middle_station, end_station, flat, flat, left_turn_5 → (51,67) d1 flat ×2 → (51,69) LIFT: chain flat_to_up_25, chain up_25 ×5, up_25_to_flat → apex 208 @(51,76) crest&drop: flat_to_down_25, down_25×5, down_25_to_flat → (51,83) z112 flat ×1 → (51,84) right_turn_5 → (54,86) d2 EAST BAND (d2, y86): flats ×6 → cursor (61,86) KIT-E: [flat_to_up_25, up_25, up_25_to_flat, left_vertical_loop, down_25, down_25, down_25_to_flat] → advances 6? count pieces/tiles: 3 rise tiles + loop 2 tiles + 2 falls + 1 fall = 8 tiles; lateral drift +1 (left loop from dir2 = dy+1): positions… end cursor x = 61+8 = 69?? each piece's dx varies but totals: flat_to_up_25 dx1, up_25 dx1, up_25_to_flat dx1, left_vertical_loop dx2 (dir2: (2,1)), down_25 dx1, down_25 dx1, down_25_to_flat dx1 = total dx 8 ✓ dy total +1 → east band line becomes y87 after kit! → cursor (69,87) d2 z112, LINE SHIFTED to y=87 ✓ SAFE. flats ×12 → (81,87) right_turn_5 placed (81,87): δ(2,-3) → (83,84) d3 ✓ SAFE (y84>75 ✓) EAST COLUMN (d3): flats ×3 → (83,81)? From (83,84): flats advance -y: (83,83),(83,82),(83,81) = 3 → cursor (83,81). Hmm keep column x83: lake-x includes 83!! At y≥77 still safe. Column descent to corner-start for west leg... right_turn_5 from d3 δ(-3,-2): place when ready: want land ≥x≥?, y=77+: e.g., cursor (83,79) → lands (80,77) d0 ✓ SAFE y77. So EAST COLUMN: flats ×2 → (83,81)?? Let me recount: after S-turn cursor (83,84); k flats → y 84-k; want corner at cursor y=79 → k=5 flats ((83,83)..(83,79)); corner δ(-3,-2) → (80,77) d0. WEST LEG (d0, y77): From cursor (80,77): flats decrement x. Target: corner-left start such that final approach lines up into (43,64) node. Tail geometry (worked earlier): south-dive corner-chain: [left_turn_5 from d0] δ(-2,-3) lands (X-2, Y-3) d3; dive south on x=X-2; flats until Y'; [left_turn_5 from d3] δ(3,-2) → lands d2 at (x+3, y-2)=final pre-station corridor MUST be y64: so Y' - 2 = 64 → Y' = 66; flats along the dive: from (X-2, Y-4?) ... precise: after first corner lands (X-2, Y-3) d3; each flat decrements y: need reach cursor (X-2, 66): number of flats = (Y-3) - 66 = Y-69. Then [left_turn_5] → (X+1, 64) d2 — WAIT δ(3,-2) applied at cursor (X-2,66) gives (X+1,64). Then final flat(s): to reach cursor (43,64): flats needed from X+2 .. 43 inclusive: count = 43 - (X+1) = 42-X. Then close via "flat" placement. Choose X: west-leg runs from x=80 (cursor) down to X. If X = 41: first corner lands (39,73)?? δ(-2,-3) from (41,77) → (39,74)... careful: FIRST corner placed AT CURSOR (X,Y)=(41,77) means δ(-2,-3) applied → land (39,74) d3?? But earlier v1 the same call from (41,76) landed (39,73). Hmm in v1 I called left_turn_5 with cursor (41,76) and result landed at... place_pieces reported cursor AFTER piece = (39,73) dir3 ✓ consistent with δ(-2,-3) → (41-2, 76-3) = (39,73) ✓. Now west-leg base is y77 → dive column x=39, y from 74 downward: flats: 74→66: 8 flats → cursor (39,66); corner-left (δ 3,-2) → (42,64) d2 ✓; flat → (43,64); CLOSE. West-leg fill: from cursor (80,77) target corner-start cursor (41,77): tile-span = 80-41 = 39 tiles of track on this leg: composition incl. Kit-W (+8 span, +1 lateral drift — direction: choose RIGHT_vertical_loop from d0: δ(-2,+1) pushes north y+1→line y78: LAKE-SAFE? crossing l… (9281 chars)

The vertical loop does NOT accept flat entry — it "enters at 25-up slope" per the error?? Reading: "piece enters at 25-up slope but the track here is flat; add a slope transition piece first". So the LEFT_VERTICAL_LOOP piece REQUIRES entry at up_25 slope! I.e., in this game, loops are entered while climbing. So kit revision: rise with climb that ENDS at up_25 slope (not flattened): [flat_to_up_25, up_25] → slope2 → left_vertical_loop (enters 25-up ✓) exits slope6 z = start+8+16+0 = +24? Loop dz 0 relative to its own node... Let me recompute: enter loop at height H (end of up_25), exit at H+0 slope6. Then falls: down_25 ×2 (-32) → down_25_to_flat (-8): total: +8+16-16-16-8 = -16?? Net -16 ❌ under ground risk... Fix: enter loop via [+8 flat_to_up_25][up_25 (+16)] loop dz0 [-8? ...] → need net 0: additional rise after falls, or pre-rise: put ONE more up_25 BEFORE loop: total climb +40; falls max available from slope6: down_25 ×j then down_25_to_flat = -(16j+8); want net 0: 40 = 16j+8 → j=2 exactly ✓✓ (+40 − 40 = 0)!! NEUTRAL KIT v3: [flat_to_up_25 (+8)] [up_25 (+16)] [up_25 (+16)] → loop enters s2 @H=start+24, hmm loop requires slope_in == up_25 (code 2) ✓ after an up_25 ✓; loop dz=0 exits s6; [down_25, down_25] (-32) [down_25_to_flat] (-8) ⇒ NET 0 ✓✓✓ SPAN: 3 tiles rise + 2 loop + 3 falls = 8 tiles SAME span as before!! Just the extra up_25 replaces up_25_to_flat. And no drift change. BUT WAIT: is slope6→down_25_to_flat valid directly after loop's exit (slope_out 6) ✓ yes pieces consume slopes sequentially. Also note current cursor state: we're mid-kit having placed up_to_flat + loop-rejected at index 33. State cursor (63,86) z144 — hmm z144?! That means the two rise pieces added 8+16 = +24 over baseline 112 → 136, then up_25_to_flat +8 = 144 flat. Correct — it sits where my ORIGINAL kit had flattened. Now to adapt WITHOUT undoing everything: replace "up_25_to_flat" plan: undo the last piece (up_25_to_flat) → back to slope2 z136 at (62,86)? then place [up_25] (+16 → z152 slope2), then loop, then 3 falls. z bookkeeping: pre-kit baseline was 112@flat. Rise: +8 (120 s2), +16 (136 s2), now adding another +16 (152 s2). LOOP dz0 exit s6 @152. Falls: down_25 (136 s6), down_25 (120 s6), down_25_to_flat (112 s0) ✓✓ lands at baseline PERFECTLY. Drift still +1 (y86→87) ✓ plan unchanged downstream. Execute: undo once, then place corrected sequence from index 33 onward: [up_25, left_vertical_loop, down_25, down_25, down_25_to_flat]. Then continue east band flats ×13 etc.

Kit works: lands (68,87) z112 baseline, drift +1 to y87 as planned. Now continue: flats ×13 → (81,87), right_turn_5 → (83,84) d3, flats ×5 → (83,79), right_turn_5 → (80,77) d0. Then west leg with kit W in corrected form. West leg kit W (heading d0 at y77): [flat_to_up_25(+8), up_25(+16), up_25(+16), left_vertical_loop(δ -2,-1 from d0), down_25, down_25, down_25_to_flat] → span 8 tiles, drift y 77→76 ✓, net z 0 ✓. Full remaining plan: - flat ×13 → (81,87) - right_turn_5 → (83,84) - flat ×5 → (83,79) - right_turn_5 → (80,77) d0 - flat ×10 → (70,77) - KIT-W → ends (62,76) - flat ×6 → (56,76) - HILL-C: flat_to_up_25, up_25, up_25_to_flat, flat, flat_to_down_25, down_25, down_25_to_flat (7 tiles) → (49,76) - flat ×8 → (41,76) - left_turn_5 → (39,73) d3 - flat ×7 → (39,66) - left_turn_5 → (42,64) d2 - flat → (43,64) That's ~50 more pieces; split into two calls with a checkpoint.

Exactly on plan: (80,77) d0. Now the west leg with kit W. Batch: flat ×10 → (70,77) KIT-W: flat_to_up_25, up_25, up_25, left_vertical_loop, down_25, down_25, down_25_to_flat → ends (62,76) flat ×6 → (56,76) HILL-C (7) → (49,76) flat ×8 → (41,76) Check positions between via state after.

Cursor (49,76) — that's after KIT-W + flats ×6, hill C appears NOT placed? Let me count: my call had 10 flats, then kit (7 pieces: flat_to_up_25, up_25, up_25, loop, down_25, down_25, down_25_to_flat = 7), then 6 flats, then HILL-C started with flat_to_up_25... The result cursor is (49,76) z112 slope0 which is exactly after flats×6 following the kit. That means the call stopped early?? placed_this_call: 30 = 10+7+6 = 23... no it says 30. Hmm: 10+7+6=23; remaining 7 = the hill's 7 pieces... but cursor shows slope0 z112 at (49,76): if hill completed: hill spans x55→49 wait starting from (56,76)... let me recompute positions: Start (80,77). 10 flats → (70,77). Kit-W from d0: flat_to_up_25 dx-1 → (69) z120 s2; up_25 → (68) z136 s2; up_25 → (67) z152 s2; left_vertical_loop dx -2 → (65,76)? drift y77-1 = 76 ✓ dz 0 exit s6 @152; down_25 → (64) z136 s6; down_25 → (63) z120 s6; down_25_to_flat → (62) z112 s0. Kit ends (62,76) ✓. 6 flats → (56,76). Hill-C: 7 pieces span dx -7 → ends (49,76) ✓✓ matches reported cursor! total = 10+7+6+7 = 30 ✓ ALL PLACED including hill. I miscounted earlier; fine. Now tail: flat ×8 → (41,76), left_turn_5 → (39,73), flat ×7 → (39,66), left_turn_5 → (42,64), flat → (43,64). Then closing piece.

Circuit closed with 2 vertical loops. Test it.

Troubling signs: - excitement: null, intensity: null, nausea: null, "tested": false - ride_time: 780 (vs 55 in v1), ride_length 3124 (vs 474), average_speed 155920884 — absurd - num_drops: 29?! num_inversions: 7?! Something's off. The train seems to have gotten stuck/oscillating or the sim is counting something weird. Ride time 780 seconds with looped:true and walked_pieces 106... The train may be running abnormally slow through the loops or, worse, the test didn't complete a proper circuit rating. Wait — maybe the train stalled somewhere (couldn't complete the loop at low speed) and the sim ended before a full successful cycle. max_speed same as v1 (941155). Actually average_speed 155920884 units = insane; likely artifact of incomplete test. Possibility: the loops are being traversed REPEATEDLY? "num_inversions: 7" though I placed 2 loops... Perhaps vertical_loop pieces count each car? Or the "loop" piece acts like... hmm. Or: my two vertical loops create a situation where the track physically self-intersects?? The loop drifts ±1 tile; loops occupy 2 tiles lengthwise spanning tall visuals but net flat footprint. Multiple crossings within a tile could confuse. But then it would crash (crashed:false). More likely: the TEST TIMED OUT because the train ran very slowly in some section — e.g., approached the east-band loop too slowly, rolled back (RCT2 allows rollbacks), oscillated, taking forever → sim hit tick limit while not completing enough cycles for rating. In v1 the full lap was fast; now with loops losing speed, average dropped. Actually average_speed astronomically high suggests measurement glitch when vehicle never finishes... Whatever the cause: hypothesis = loop entry speed insufficient OR mid-circuit energy starvation after lift apex reduced... Wait, apex unchanged 208; added loops consume ~40+ each... The loops sit mid-course where v1 had hills — modest approach speeds (~35-40 mph). A RCT2 steel twister vertical loop needs decent entry speed, else stall/rollback (which is safe but ruins pacing + can strand train). Fixes: 1. Reorder circuit so the FIRST element after the big drop is a loop (max speed there). 2. Add a booster mid-course to guarantee pace. 3. Raise lift height (+1-2 up_25). Simplest robust fix: add BOOSTERS before each loop site (booster speeds up to ~25) AND/OR bigger drop. Boosters are explicitly encouraged by the prompt ("A booster is the fix for a layout that runs out of energy and valleys"). Plan #3 changes (keep everything else identical): - Insert a booster right BEFORE each loop kit on the flats preceding the rise (speeds train up to 25 over its run-in). Actually booster accelerates "up to its speed" while ON that piece; passing through at less than target speed gets accelerated. Place ~5-8 tiles ahead of the kit on flat runs. Also one more possibility: LOWER expectations first — bank THIS build's rating issue aside, take screenshot to check visuals? The result says tested:false & null ratings, no score gain. v1 score remains banked (best_result keeps highest). Let me redesign more aggressively but safely: V3 DESIGN: - Keep station/lift/drop skeleton. - Move LOOP #1 to immediately after the main drop bottom: at (51,83)→(51,84)... entering straight down 25° then flatten → we lose time; place loop right after "down_25_to_flat" + 1 flat: floor section heading d1 (+y): loop from dir1 needs geometry: query? From symmetry: dir1 left_vertical_loop δ(M(2,1)) where M(a,b)=(b,-a): M(2,1)=(1,-2) → (dx1, dy-2)? So entering the loop climbing north pulls the exit 2 TILES SOUTH?? The loop knots back — positionally fine (open area x51 y84-88 clear ✓ lake far). Then falls -40 need space: exits s6 still going d1 north, 3 more tiles: to (52?,89)... fine. Hmm but floor z112 → loop enter at slope2 (must CLIMB into loop per error message!). At floor level climb to z136 via the kit rise THEN loop: enters loop at LOW height — the loop itself provides inversion even from moderate speed IF train has moment… (9732 chars)

Cursor (82,84) d3. I expected (83,84) — off by one (13 flats after kit: 68+13=81 then corner → 81+2=83... let me recount: kit ends (68,87); flats ×13 → 69..81 → cursor (81,87)? then corner (2,-3) → (83,84). Reported (82,84): means flats placed =12 or the count in my call: after down_25_to_flat: flats listed: "flat" ×12? Let me count my pieces array: [flat,flat,flat,booster,flat,flat] =6; kit =7; then flat×13?? I wrote 13 flat entries? The tail shows right_turn_5; resulting cursor 82 vs predicted 83 — whatever, downstream needs minor adjustment anyway since east column just goes -y. Position now (82,84) heading d3 (-y). East column: corner-right δ(-3,-2) must land x≥80-y77+; want landing (79,77)? y-column current x82: flats ×5 → (82,79); corner → (79,77) d0 ✓ SAFE (y77). Then west leg from (79,77): total span to corner-start (41,76) = 38 tiles now (was 39!): composition: F1 slots: flat×8 + booster =9 → (70,77)... wait: 79-9 = 70 ✓ same as before minus one front tile: use [flat ×8, booster]; KIT-W span8 → (62,76); flats ×6 → (56,76); HILL-C 7 → (49,76); flats ×7?? remaining to reach x41: 49-41 = 8 → keep flats ×8 ✓ TOTAL: 9+8+6+7+8 = 38 ✓✓ ends (41,76).

Still null ratings / tested:false. Now num_drops 127, inversions 42, ride_length 10038, air_time 742, average_speed 5e8, max_speed 1.19e6 (higher than v1's 941155 — boosters contribute). Ride_time 780 again = sim limit. Interpretation: the train IS running the circuit (walked all 104 pieces), it loops around... but doesn't complete within the tick budget? OR something pathological: "num_drops 127" and "inversions 42" with air_time 742s?!? That smells like the vehicle is being measured across MULTIPLE laps and physics is going haywire — 42 inversions from 2 loop pieces?? Unless... the vertical_loop pieces in THIS game cause repeated counting per crossing. Wait — maybe the booster pieces are at fault: booster accelerates up to 27 (max_speed 1193914 vs v1 941155). With sustained boosters each lap, speed builds every pass → eventually insane speeds → track derailment simulation garbage → test never settles. Also intensity readings null because rating only computed on "tested" success. Actually more mundane hypothesis: the ride simply never RETURNS to station cleanly for re-dispatch: the train completes a lap but the game waits... no, lap detection works via walked_pieces looped:true. Hmm, "num_drops" 127 & airtime 742 suggests super long runtime with massive hills. Let me hypothesize the actual failure differently: THE TEST TRAIN get stuck NOT reaching enough speed somewhere and rolls back repeatedly (rollback → oscillation until friction dissipates → then chain lift grabs it back up from where?? rollback on non-chain sections → train stuck oscillating between two points forever = ride never finishes cycle = timeout). Where could rollback happen? Loop #2 on west leg: entry after booster(27) + climb +40 before loop... loop consumes ~40+; approaching from east column turn at modest residual speed... booster helps. BUT here's a real red flag I overlooked: my KIT-W has TWO up_25 climbs BEFORE the loop: rise sequence [flat_to_up_25, up_25, up_25] then LOOP. In RCT2, entering a vertical loop FROM AN UP-SLOPE is unusual — wait the error earlier explicitly demanded slope-in == 2 (up_25) ✓ game enforces that here. Fine. Energy: enter kit zone post-booster(27 speed-units ≈ decent); climb 40; loop; exit s6 fall 40 net-zero height BUT friction losses… loops in RCT need v ≥ sqrt(g·r·~5?) roughly equivalent to ~40-50 units of height. The +27 booster speed (~27 mph?) might be barely insufficient! Approach smarter: measure! Get DIAGNOSTIC data: use shorter finish_and_test ticks to see partial telemetry? The report shows same shape regardless... Better idea: SIMPLIFY TEST HYPOTHESIS by building a variant WITHOUT loops but WITH boosters. If ratings compute fine → boosters fine, loops are the problem. If still null → boosters are the problem. Binary search costs ~5 min per iteration though; time budget matters (used maybe 12 min so far). Actually WAIT. Reconsider completely: v1 (no boosters/no loops) rated FINE. Both loop/booster variants FAILED with tested:false + wild stats. The common new element across failures... loops appear in both failed builds; boosters only in second. So loops are prime suspect. Why would vertical loops break testing? THEORY: vertical_loop pieces cause the PHYSICS ENGINE to place multiple vehicles weirdly? No... Theory: the train ENTERS loop too slow, stalls mid-loop, ROLLS BACK through the loop piece backwards... causing orphan/infinite oscillation without progress. walked_pieces counts cumulative traversal events (104+ repeats)... "circuit.looped true, walked 104" hmm equals total_pieces exactly = actually consistent with one clean lap?? Then why not tested?! Maybe the test requires the train to FULLY CIRCULATE back into station AND the game's tester checks "complete path within tick budget": if the train crawls (very low avg speed due to stall-recovery phases), 780s ride_time might be just ONE slow lap?? ride_length 10038 vs v1 474!! 10038 seconds?? ride_time 780. v1: length 474/ride_time 55: length/time = 8… (13865 chars)

Floor at (51,83) d1 z112. Now the loop kit right here: [flat, flat, flat_to_up_25, up_25, up_25, left_vertical_loop, down_25, down_25, down_25_to_flat] — entering loop after just 1-2 tiles from the drop floor = maximum speed.

Excellent! The loop landed with cursor (50,89) z152, slope 6 (down_25), dir STILL 1 (+y). So from d1, left_vertical_loop displaced (dx -1, dy +2): net forward. Perfect — it stayed going north-ish. Now falls: down_25 ×2 then down_25_to_flat → land flat z112 at (50,92). Then continue north on x50 line: more track, corner east, etc. adapt downstream to whatever the cursor shows. After kit: cursor ~(50,92) d1 flat z112. Continue: flats/hills north to ~y100, turn right (d2), east band ~y102-104, down x≥86, west leg back to y77-ish corridor, tail identical. Downstream plan targets: - North run: [flat ×6] → y98 - HILL-A span7 → y105 - right_turn_5 δ(3,2) → lands (53?,107) - EAST BAND: flats ×16 w/ S-BEND insert: s_bend_left replaces 3 flats (drift -1?) — do the simpler: flats only for reliability? Add ONE s_bend for spice if space allows... keep simple first: flats ×18 → x~72; HILL-B → x79; flats ×2 → corner-start x~84: right_turn_5 δ(2,-3) → (~86,y104) — wait need exact numbers. I'll checkpoint after each chunk and fill with extra flats as needed rather than over-planning: adjustable filler = flats. Let me just build chunk-by-chunk and steer via state reads.

Cursor (53,108) d2. East band along y108 (way north of lake ✓). Need to reach x~84 then turn south. Plan east band: flats + hill + s_bend for variety: - flat ×8 → (61,108) - HILL-B span7 → (68,108) - flat ×6 → (74,108) - s_bend_left δ(3,1): from dir2 → drift to y107? or y109: dir2 s_bend_left δ(3,1) = ends y109 — LAKE-SAFE obviously (y109). But mid-band lateral shifts complicate the subsequent corner coordinates — fine, adaptive. Actually keep it predictable; skip s-bend here and save it for west leg where line is looser. - flats ×10 → (78,108)... target corner-start such that lands x≥86 at its y-3: corner δ(2,-3) placed at (84,108) → (86,105) ✓ SAFE. From cursor 53: fill 31 tiles to reach 84: [flat ×8] (61) + HILL-B 7 (68) + [flat ×16] (84) = 31 ✓ exactly. Then right_turn_5 → (86,105) d3.

East column: corner landed (86,105) d3; 6 flats → (86,99); corner δ(-3,-2) → (83,97) d0 ✓ x83 y97 SAFE. Now west leg from (83,97) heading -x at y97 — must get to tail anchor corridor y77-ish. Long way south: need east-column extension... TOO SHORT: west band at y97 would cross the lake-x region at y97 ✓ fine (lake max y75). Actually WAIT: westbound along y97 crosses lake-x zone only if y∈[55,75] — y97 is far north = SAFE all across!! So no need to descend AT ALL: run west leg directly along y97 back toward station longitude, then dive south on x~39!! Even better — shorter circuit, plus variety. West leg plan: from (83,97) to corner-start ~(41,96/97): span ~42: - flat ×6 → (77,97) - S-BEND LEFT for spice: s_bend_left from d0?? Need geometry... skip; use HILL-C instead: - HILL-D span7 → (70,97) - flats ×10 → (60,97) - KIT-W2 loop attempt #2! Westward line speed is moderate by now (post hills)... risky again?? Previous loop failures happened MID-BAND after boosters even failed... hmm actually fail builds had loops in d0/d2 mid-course contexts identical-ish. The single successful loop was IMMEDIATELY post-drop. So second loop here = HIGH RISK of failing test again. DECISION: NO second loop. Instead pure hills + banked turns? Banking unverified too. KEEP IT SIMPLE & BANKABLE: fill with v1-proven elements (flats + zero-net hills). - flats ×8 → (52,97) - HILL-E span7 → (45,97) - flat ×3 → (42,97)? Then corner-left placed AT CURSOR must land dive-corridor correctly: left_turn_5 from (41,97): lands (39,94) d3: dive: flats until y66: count = 94-66 = 28 pieces!! LONG column dive straight down x39 — boring but FINE, or spice with TWO hills: 28 = 7+7+7+7: FOUR hills?? excessive G + slow train alternating... Use 2 hills + flats: 7+14+7 = 28 ✓: [HILL-F][flats ×14][HILL-G]. Check total span before corner: from cursor (83,97): 6+7+10+8+7+3 = 41 → cursor (42,97); ONE more flat → (41,97); then corner-left... let me recount my listed fills: 6,7,10,8,7,3 = 41 tiles ending x = 83-41 = 42. Add 1 flat → cursor (41,97) exactly then [left_turn_5] → (39,94) d3. Dive total from y94 to approach-corner Y': final pre-station turn: [left_turn_5] placed at (39,Y') where Y'−2 = 64 → Y' = 66 ✓ (station row untouched!): flats needed: 94→66: after corner lands cursor (39,94) first flat → 93 ... reach 66: k = 94-66 = 28 ✓ matches fills above. Then [left_turn_5] → (42,64) d2; [flat] → (43,64); CLOSE. Verify lake-safety of dive column x39: 39 < 68 ✓ always safe any y ✓✓.

"Twister Roller Coaster 1 in the way" at index 10 (up_25_to_flat) — track collision! Something intersects. Wait — index 10 = up_25_to_flat? Sequence: 8 flats (x59..52), flat_to_up_25 (51,97), up_25 (50,97), then up_25_to_flat → rejected: "in the way". Hmm — what's at (49,97)? NOTHING built yet there... unless my EARLIER east-band hill area overlaps?? No... OH WAIT: HILL-E's rise pieces: the rejection is for up_25_to_flat at position cursor x49 — but what occupies that node? Could be the WEST LEG of v1?? No, demolished. Hmm, think: "Twister Roller Coaster 1 in the way" might mean a PIECE ALREADY PLACED of THIS SAME RIDE occupies target space — e.g., diagonal crossing?? Our circuit hasn't crossed anywhere... EXCEPT: wait, positions around (49,97): nothing prior... Let me check whether HILL-D earlier actually placed where I thought! Recall previous call ended (60,97): fills were [flat×6→77] HILL-D(7)→70, flats×10→60 ✓ consistent reported cursor ✓ no anomalies... Then this call: 8 flats from 60: 59,58,...,52 ✓; ftu25 @(51); u25 @(50)... wait previous call's piece #17 = up_25_to_flat part of HILL-D ending (68,97)? Consistent. So why collision AT up_25_to_flat from (50,97) s2 going to (49,97)?? The up_25_to_flat piece spans its OWN tile (50,97)+node into next (49,97). What could occupy (49,97) or the elevated segment ABOVE it... OH!!! I BET I KNOW: THE Z-VALUE mismatch!! Reported cursor z136 slope2: after 8 flats + ftu25 (+8) + u25 (+16) = z136 ✓. The up_25_to_flat completes to z144. Is ANYTHING at height ~140-144 near (49..48, 97)?? The EAST-COLUMN/HILL-B vicinity: East band was along y108-109... NO. Hold on — check LIFT/APEX region: lift column x51 y69-77 apex... not here either. Wait, maybe the issue is DIFFERENT: "Twister Roller Coaster 1 in the way" = the game's name for OUR ride object being an obstacle — i.e., SELF-INTERSECTION detection triggered by TRACK BELOW: the up_25_to_flat geometry possibly needs a support/space colliding with the LOOP KIT overhead?!? LOOP-KIT location: y84-92 range near x50!!! THE FALLS+FLATS after loop ran north through x50, y89-103!!! My southbound... wait west-bound leg is CURRENTLY at (50,97) heading -x: the station/LIFT column x51 crosses y83-108 REGION?? YES: the lift is at x51 column y64-77 AND the post-loop flats ALSO at x50/51 running NORTH y83→108!!! These are PARALLEL-but-same-column PROXIMITY but they never intersected until NOW: the current westward turn approach pushed track across x51,y97 — DIRECTLY ABOVE/THROUGH the post-loop straight which occupies (50,96)-(50,103)... CONFIRMED COLLISION RISK: earlier north-run pieces: after loop kit: falls at (50,90),(50,91),(50,92) then flats (50,93),(94),(95)... then (50,96),(97)... UP TO (50,103)! And now westleg came down to cross X=50 line AT y97: piece ftu25@ (51,97)-u25@(50,97) COLLIDES with pre-existing (50,97) node ✗✗✗. WAIT how did flats×8 pass through x51-56 though?? Positions 59..52: pieces at x59...x53 passed y97 across columns x59-x53: did those columns have existing track? The dive/station columns are x39 & x44-47 only; lift x51 spans y64-77 NOT y97 ✓; post-loop straights x50 span y89-103 ✗✗ x50 IS IN THAT RANGE — and I CRASHED exactly when hitting x50! Hmm so how did flat @(51,97) get ACCEPTED then (piece index 8-9 accepted!)? Because (51,97) unoccupied ✓ (the north straights sit on x50). Then u25@(50,97): OCCUPIED by north-run flat!! Should have rejected THERE ("index 9")... unless overlap-tolerance allowed same-node different-height?? u25 @ (50,97) climbs +16 above: nodes at different heights CAN share tile ✓ game allows multi-level crossings?? Apparently (50,97) had a flat @112 while new u25 starts @120 rising — CROSSING PERMITTED vertically?? Then up_25_to_flat spanning forward (49,97) at ~z136-144: WHAT occupies (49,97)@~144?? Hmm maybe supports/footprint conflict with the PREVIOUS flat@(50,97)'s support column?? Whatever the precise rule: AVOID stacking on the x50 corridor. Current partial placement halted mid-hill w… (6684 chars)

Rejected on index 2 — so flat #0 and #1 placed (x51, x50). WAIT: flat at x50 accepted?! That contradicts... unless the earlier collision interpretation is wrong. Hmm: pieces: index 0 → (51,97), index1 → (50,97), then index2 (49,97) REJECTED "in the way". So the blocker is at/near (49,97) — NOT x50! What's at (49,97)?? OH NO. I bet it's the FINAL FLATS from an EARLIER segment... think about v-current placements near x49 y97... west-leg HILL-E started at (60,97)... nothing at 49... Hmm wait, what about... THE EAST COLUMN! Earlier this build: "right_turn_5, flats ×6, right_turn_5" landed cursor (83,97): pieces during that: corner@(84,108)→(86,105); flats ×6 @ (86,105..100)? positions (85? no d3 heading -y: x stays 86: y104..99); second corner δ(-3,-2) → lands (83,97) ✓. Nothing at 49. What about y97 crossings of... THE DIVE?? There IS no dive yet. Track DOWN-LEG (previous section before east column?) no... Hmm — could the obstacle be support-footprint VIRTUAL blocking because of the LIFT hill column?? Lift occupies x51 y64-77 tall structure — not here. Wait wait. Maybe I mis-tracked which segments ran through (49,97)-ish region... Post-loop north straights: cursor after kit falls was (50,92)... then "flat×4" → (50,96)... HOLD ON recount that call: ["down_25","down_25","down_25_to_flat"] → (50,92); then flats: my call listed flat×4 THEN hill... reported end (50,103). flats×4: (50,93),(94),(95),(96); hill: ftu25(50,97)!!! u25(50,98), u25tF(50,99), flat(50,100), ftd25(50,101), down25(50,102), d25tF(50,103) ✓✓ ends 103 as reported!! SO (50,97) & (49,97)... the north-run occupies x50 y89→103 INCLUDING (50,97)@z112-flat ✗ AND YET just now a NEW flat successfully took (51,97) + (50,97)!!! Double-checking with game acceptance: they placed WITHOUT error?! Because same-node same-height stacking is... rejected normally!! Unless (50,97) node actually was z112 VACANT: north-run hill consumed (50,97) with ftu25(z120-slope2) not flat... NODE TILE OCCUPIED by track regardless of height—should reject!!! Unless north-run doesn't actually pass through (50,97)!!! Recheck loop-kit geometry: loop left cursor (50,89) s6; falls: down_25 → cursor next-tile... The CURSOR ADVANCES along the TRACK DIRECTION: slope6 + d1: down_25 moves cursor +1 in y each?? Or does it follow (dx,dy)=(−1,+2)-ish STAGGERED slope path?! If down-25 sections drift laterally per-cursor like turns did, actual tiles differ!! Reported cursors only show END positions; interior tiles unknown to me!! CONCLUSION: MY TILE-ACCOUNTING IS UNRELIABLE for slope/turn interiors. The safe play NOW: probe with valid_next_pieces / undo the 2 placed flats, then route AROUND: shift westbound line OFF y97 — e.g., back off and dive EARLIER via turning LEFT immediately?? Can't turn left mid-line without geometry... SIMPLEST ESCAPE: re-route using another LEFT TURN NOW to drop south BEFORE the blocked zone: currently cursor (52,97) after undone... state now: pieces 115, cursor (52,97) d0. Option: place [left_turn_5] δ(-2,-3) → lands (50,94)?? ANOTHER collision w/ north-run corridor ✗ risky. Option: BACK OFF the whole y97 line further WEST isn't possible (blocked band unknown extent). RETHINK ROOT CAUSE instead: maybe blocked zone = exactly where NORTH-RUN'S HILL-B/tiles... The rejection at (49,97) flat-at-z112: north-run's post-loop FALLS+FLATS occupy SOMEWHERE around x48-50 y88-96 area probably STAGGERED. The flats BEFORE hill-B were pure straight d1x50: y92→97?? if falls staggered... ugh. PRAGMATIC: get_valid_next_pieces at cursor + MOVE ON differently: try placing ONE more piece [flat] → if rejects again at SAME location... Actually current pieces_placed=117 INCLUDES (51,97),(50,97) both accepted: PROBE forward with single flat → likely reject again (blocker ~(49,97)). Then UNDO those 3 extra and take the DIVE-SOUTH-EARLIER option with corner placement somewhere CLEARER: corner-left start must be at (X,97) whose landing (X-2,94)+dive-column X-2 avoids x44-51 stack zone: choose X=42 → lan… (5016 chars)

CONFIRMED: the westbound corridor is blocked at (49,97) even on flats — so the blockage sits around x49-48 at y97 (or higher). The earlier x50/x51 "placements" pass but the node beyond rejects. So something occupies tiles between (48..43,~97) — almost certainly the north-run's diagonal/straights cluster near x47-50, y92-104... wait that runs x50 exactly; passing x50 twice without rejection but failing at 49 strongly suggests an interior STAGGERED piece at ~(49,96-98). Rather than probing further, commit to the early-dive route from current position: undo ×2 → back to (52,97); then flats ×10 → (42,97) [passes through blocked zone?? NO — moving WEST crosses x51,50,49,...: BLOCKED AT x49!! ✗✗✗ DAMN: diving via corner at x42 requires REACHING x42 through the SAME blocked corridor!!! ⇒ MUST dive EAST of the blocker: turn left/dive-start IMMEDIATELY east of x50-ish… Options from cursor after-undo (52,97) d0: [A] place corner-left NOW (at cursor 52): δ(-2,-3) → lands (50,94) — inside suspected stagger-zone ✗ risky. [B] BACK OFF with RIGHT turn heading NORTH (+y)?? d1 north along x52: clear zone ✓ but wrong direction for closure... [C] CROSS THE GAP DIFFERENT WAY: dive column MUST start ≥ (some clear X). Between x44(?) and x52 unclear which columns safe. DEEPER PROBE NEEDED: check what valid_next_pieces says & scan for blockers using small forward steps w/ immediate undo? Expensive... BETTER IDEA — LOOK FROM ABOVE: SCREENSHOT! Visual diagnosis in one call ✓✓ DO THAT NOW to see actual track layout + the blocker.

HUGE revelation! The screenshot shows: - The lake is in the CENTER of the map (~tiles 68-85, 55-75 confirmed) - My track: a compact layout mostly NORTHEAST of the lake — the track is MUCH SMALLER than I imagined. The lift column, loop (visible as a circle!), and bands hug close together. - WAIT: my track appears to be positioned EAST of the lake, x~52-83?? Actually looking at it: station appears at the bottom-left (that's the little station platform with trees at bottom-center-left of the map)... hmm, actually the bottom-left structure with white platform = station at (44,64)? And the big yellow circuit sits NORTHEAST of the lake. CRITICAL INSIGHT: The visible track is FAR SMALLER in extent than my coordinates suggested — the whole circuit spans maybe x50-83, y64-108?? That can't be: I placed north band to y108, west leg to x83... The screenshot's yellow path shows: station → lift going NE... loop visible (the pretzel circle!) → long straight east → big rectangular return... Compare to expectations: the loop pretzel is at map-top-center ~x50,y88 region ✓; east band rectangle = y97-108 x52-86 ✓; west leg y97 heading back... the screenshot shows the west leg running down-left toward... it seems to END near x49 (the "blocker" region shows track SQUEEZING — I can see the return leg coming back WEST at y97 and stopping abruptly around x49-50). AND — the ORANGE/RED segment at map top (~x52,y70ish) = the LIFT CHAIN portion going up the column... The layout seems consistent. The blocker: looking closely at the west leg at y97: it comes back west and there's a visible GAP/dense region around x44-50, y~92-100 — where...?? I see the NORTH-RUN straights (x50 column, y89-103) forming a vertical line, and the west leg approaching it at y97 CROSSING... they nearly touch around (49-50,97) — indeed the collision: the north-run hill-B? no hill-B was on EAST band... the NORTH RUN after loop: (50,84-103) vertical column, and hill-A on that column (y96-103)... So the west leg at y97 hits the x50 column area where hill-A's UP-slope spans elevated nodes — the collision at (49,97) though?? Hmm, whatever occupies (49,97): looking at the image, around that area there's the track coming from the loop's exit curving... the LOOP exits and its falls+straights run NORTH on x50 — BUT the falls may stagger slightly WEST (left loop from d1 displaced dx-1!) — the falls/flat pieces could sit at x49-ish for a few tiles!! left_vertical_loop from d1 = dx -1: so loop ends at x50 (we saw cursor 50,89) — but the DOWN_25 pieces after exit: does their interior stagger? The reported cursor stayed x50 for all subsequent... only END-cursors known; interior node tiles of down-slope pieces might occupy (49,*) transiently?? Unlikely (straight pieces don't zig). Let me look again... At the left side of the track cluster near y~90-95: I see the track descending from the loop toward bottom-left then making a LEFTWARD hook (around x49-50,y93-96)?? There's a visible S-curve/kink in the west leg's start... OK — enough forensics. STRATEGIC DECISION: The current build is 90% complete and STUCK only on the final ~50 pieces (west leg tail blocked at x49). Two options: (1) Continue west leg by JUMPING the corridor: dive EARLIER — turn left NOW from cursor... but cursor currently sits at (50,97) d0 mid-line after the last rejection (pieces 117: two flats placed (51,97),(50,97)). From (50,97) I CANNOT advance west (blocked at 49). CAN I turn? From d0, left_turn_5 → δ(-2,-3) → lands (48,94): inside suspected blockzone ✗. right_turn_5 → δ(-2,+3) → (48,100) d1: heading NORTH along x48: is x48 column clear?? North-run column = x50... x48 likely CLEAR (2-tile gap? supports don't block). Then run NORTH on x48 a few tiles, then... this becomes a tangled detour. (2) ABANDON tail-blocking complication: this build won't close cheaply. TIME CHECK: I've spent ~half the budget. The banked v1 (5.60) stands. Rather than wrestling THIS shape, do a CLEAN REDESIGN with a MUCH SIMPLER topological foo… (10869 chars)

Even flat_to_up_25 at (49,97) is blocked — the blocker occupies the tile REGARDLESS of height (probably a support-footprint or the node occupancy is 3D-overlapping at all heights, or the mystery tile is at z136+ exactly where my bridge would go). So the tile (49,97) itself is unusable at ANY height → the x50/north-run structure's footprint claims it (supports!). RCT support structures DO block crossing underneath?? Actually in RCT you CAN'T cross under most track due to supports — matches "in the way". ⇒ Bridge must offset in Y as well: cross the x50 corridor at a different latitude where crossing is legal — but supports exist along the WHOLE column y89-103... supports only under pieces needing them: flats at z112 don't need tall supports (ground level!) — but the game's collision may include footprints regardless. Alternative: CROSS THE FLOOR COLUMN AT ITS GROUND STRAIGHT (y78-83, x51): those are z112 flats: crossing OVER at z144 at y78-79: footprint-blocking likely applies there too!! Ugh. WAIT — but v1 CLOSED FINE... v1's west leg crossed... v1 layout: north band y86-87, west leg y76-77: the west leg at y77 crossed x51?? v1 crest/floor column x51 spans y64-83!! West leg y77 CROSSED x51 y77 — the SAME column — AND v1 CLOSED SUCCESSFULLY!!! So crossing lift-column footprints IS POSSIBLE... UNLESS v1's west leg didn't actually pass x51: v1 west leg ended corner-left at (41,76)... it crossed x51 at y76 ✓ IT DID — and ACCEPTED. So footprint crossing IS legal somewhere! Then WHY blocked at (49,97)?! Specific to that tile... maybe the north-run HILL-A's supports (elevated hill at z136-144 on x50,y97-103) cast WIDER footprints?? Or... The LOOP itself! left_vertical_loop from d1: δ(-1,+2): enters (51,86)... the loop's physical extent might bulge WEST to x48-49 around y87-90!! And hill-A@(50,97-99) elevated: its diagonal support footprint could occupy (49,98),(49,99)... Honestly, (49,97) blocked by SOMETHING 3D. Definitive workaround: SHIFT THE WEST LEG SOUTH one tile: instead of crossing at y97, step SOUTH first?? Can't step laterally without a turn... NEW PLAN: from current cursor (50,97) d0: place LEFT_TURN_5: δ(-2,-3) → lands (48,94) d3 — hmm inside x48 y94: unknown occupancy (blockzone?) TEST IT: single piece, read result. If rejected, try RIGHT_TURN_5 → (48,100) d1. Actually CLEANER: probe via valid_next_pieces FIRST (free, tells which catalog pieces accepted at cursor!).

valid_next_pieces = EMPTY — NO piece is accepted at cursor (50,97) heading d0. The corridor ahead is fully blocked in this direction. Escape options from (50,97) d0 with NOTHING acceptable forward: TURN pieces also rejected?? valid list empty means even turns rejected. So cursor is TRAPPED: must UNDO back to (52,97) and take a different route entirely. From (52,97) d0: try turning SOUTH earlier: left_turn_5 δ(-2,-3) → lands (50,94): probe validity. If blocked (x50 corridor region!), try RIGHT turn δ(-2,3) → (50,100): also x50 ✗ likely blocked. The x50 column poisons y89-103 laterally ±1-2 tiles. West leg can't pass until south of y~104 or north of y~88... STRATEGIC RETHINK — stop fighting geometry; REBUILD with the return leg routed where collisions CAN'T occur: the KEY MISTAKE was routing the return leg BETWEEN the lift column and everything else. INSTEAD: make the circuit's west-side excursion happen SOUTH of the station entirely: NEW SHAPE v7 (collision-free by construction): - Station (44,64) d2, entry, lift column x51 north (y64-83 with floor + loop kit to y92) - North run to y~104, east band y109, east column x84 down to y~78 - West leg at y78 going west to x~62... - THEN turn SOUTH EARLY (d3) at x62: descend y78 → y50 (passing EAST of station row, WEST of lake-x: x62 <68 ✓ SAFE any y ✓) - Turn LEFT (d3→d2, +x) at (62?,52) heading EAST?? NO — I need to approach station from the WEST going +x... WAIT simpler: return approach from the SOUTH: dive to y~46 then turn RIGHT (d3→?? from d3, right = dir0 -x?? R-mapping: R(0,-1)... M(a,b)=(b,-a): R applied = -90°? Let me re-derive from catalog: dir2 right→dir3; dir3 right→dir0; dir0 right→dir1; dir1 right→dir2. So from d3 (south, -y): RIGHT → d0 (west). LEFT → d2 (east)!!! So: descend x62 to y~48: LEFT turn (d3→d2) δ? for dir3: left_turn_5 = inverse-rotation of dir2's... dir2-left: (2,3) [2 fwd, 3 LEFT-side]: rotate to d3: forward = (0,-1): delta = 2·(0,-1) + 3·L(0,-1) where L(0,-1) = left-of-south... For d2 left=(0,+1); rotation dir2→dir3 is -90°(R): L vectors rotate too: L(0,-1) = R(0,1)?? R(a,b)=(b,-a): R(0,1) = (1,0). So d3-left-turn: 2·(0,-1) + 3·(1,0) = (3,-2) → lands +3x, -2y ✓ (matches tail experience: d3 left_turn_5 δ(3,-2) ✓✓ CONFIRMED from earlier usage!) Then from y~46 at x~65-70 heading EAST... toward lake-x at y<55 ✓ SAFE BELOW LAKE!! Continue east under the lake to x~86-90, then RIGHT turn (d2→d3) δ(2,-3)... that heads SOUTH-east away... NO I need to come BACK west to station... THIS IS GETTING SILLY. The fundamental need: approach station (44,64) heading +x from (43,64). The region west/south of station (x20-43, y20-80) is FREE. Any return leg can run THERE — completely clear of the lift/north/east structures!! Route: east column descends past the lake to the SOUTH side (y≤53), crosses EAST→SOUTH-WEST along y~48 (below lake, all x!), turns NORTH at x~30 (left from d0 = dir1?? from d0: LEFT → dir3 (catalog dir0-left→dir3 ✓), climb x30 to y~60, then RIGHT turn (d1→d2: δ(3,2)-style) at (30?,62) → lands heading +x, approach flats → (43,64) ✓✓✓ ZERO crossings of ANY structure!!! V7 COMPLETE PLAN: - station/approach/lift/drop/loop-kit: IDENTICAL to current-good core (pieces 1-27-ish through loop kit + north run + east band + east column) Current built pieces 117 - junk 2 = 115 pieces covering: station through west-leg-partial. The east column currently ENDED at (83,97) with west leg running to (60,97)... Instead of salvaging, FULL REBUILD v7 with cleaner bones (I now have the FULL proven recipe — rebuild is ~10 minutes via 4-5 batches, all coordinates pre-verified this time with EXPLICIT collision-avoidance). V7 LAYOUT (all lines chosen ≥3 tiles from any other line): 1. Station (44,64) d2; flats×2 → (49,64) 2. left_turn_5 → (51,67); flats×2 → (51,69) 3. LIFT: chain ftu25, chain u25×5, u25tF → (51,76) apex z208 4. CREST/DROP: ftd25, down25×5, d25tF → (51,83) z112 5. LOOP KIT: flat, ftu25, u25, u25, left_vertical_loop, down25, down25, d25tF → ends (50,92) z1… (9832 chars)

Core proven: loop kit complete at (50,92) z112. Now north run: flats ×4 → (50,96); HILL (7) → (50,103); flats ×2 → (50,105); right_turn_5 → (53,107).

On plan: (88,104) d3, east of lake. Now the long east column descent: 52 tiles with 3 hills: [flats ×14, HILL, flats ×14, HILL, flats ×10] = 52 ✓ → (88,52). Then right_turn_5 → (85,50) d0.

Cursor (88,53) — one short of 52 (I placed 51 pieces; miscounted one). Target corner-start (88,52): add 1 flat → (88,52); then right_turn_5 δ(-3,-2) → (85,50) d0 ✓.

(85,50) d0, south of the lake. West leg: 42 tiles to corner-start (41,50): [flats ×30] → (55,50); HILL (7) → (48,50); [flats ×4] → (44,50); +1 more? 30+7+4 = 41 → (44,50): need (41,50): flats ×5 instead → 30+7+5 = 42 ✓ → (41,50). Then right_turn_5 δ(-2,3) → (39,53) d1; climb flats ×9 → (39,62); right_turn_5 → (42,64) d2; flat → (43,64); CLOSE.

Interesting: "circuit_closed": TRUE despite the rejection on index 10 (the final flat)! The closing flat attempted to occupy (44,64) — which is the begin_station tile — rejected because occupied, but the CONNECTION itself registered: circuit closed!! 184 pieces, circuit closed. TEST NOW.

STILL null / tested:false! But now with max_speed 940045 (same as v1 — NO boosters in this build!), max_lateral_g 0.19, max_negative_g 0.04, positive 2.33, inversions 79 (from ONE loop!), drops 159, air_time 0. KEY OBSERVATIONS: - num_inversions 79 from ONE physical loop?! And num_drops 159. - air_time 0 this time. - max_lateral_g 0.19 — EXTREMELY LOW (v1 had 1.43). - Similarity now compares vs "Flashback" (ride_type 51!) at 0.33. The huge inversion/drop counts + ride_time exactly 780 (limit) suggests the test ran MANY laps: 184 pieces × ~40+ laps... The train keeps circling and the test never ENDS?? But v1 (90 pieces) rated fine with ride_time 55 = ~1 lap... WAIT. What if the TEST duration depends on... the ride being LONGER = slower lap times?? v1 lap = 55s?? A 184-piece lap at similar speeds might take ~110s, and the tester runs maybe 2 laps... 780 = ride_time LIMIT though — same value in all 3 failed tests. Suspicious constant. Alternative theory: THE VERTICAL LOOP causes the tester to run extra "bonus" cycles?? In RCT2, the ride tester dispatches MULTIPLE trains over the test... The station has capacity for maybe 2-3 trains; with loop the circuit takes longer; trains stack up; test times out... OR!!! The REAL difference between v1-rated and all-failed builds: THE VERTICAL LOOP ITSELF breaks rating. Evidence: every build WITH a loop → tested:false; v1 without → rated. num_inversions 79 = the loop's inversion flag counted PER-VEHICLE-PER-LAP × many laps... Hmm but why would many laps occur? OH WAIT — maybe I've got it: the loop pieces might make the test train RE-ENTER the station NODE repeatedly?? no... Actually — what if the loop piece creates an inversion counter that ALSO means the train's "covered circuit" tracking gets confused... whatever. EMPIRICAL BOTTOM LINE: loops ⇒ unrateable in this game build. The prompt says inversions are "ALLOWED and REWARDED" — but empirically the evaluator can't rate loop-containing rides (at least as I've built them). Since score = rated excitement, a working loop-less build beats a broken loop build. DECISION: Build v8 = v7 skeleton WITHOUT the loop, plus MORE hills (6+ airtime hills boost excitement+airtime reliably per v1: 5.60 with 18 airtime) + S-BENDS for lateral spice + maybe SECOND smaller crest variations. Actually also try replacing the loop with a CORKSCREW? Unknown-risk. Or try banked turns (positions identical per catalog!). Banked turns look cool + raise excitement typically. BUT banked turn chaining may require bank-in/bank-out pieces (adjacency unknown) — MEDIUM risk, testable mid-build cheaply: if rejected, fall back to plain turns. TIME BUDGET CHECK: ~20 min elapsed of 30. PRIORITY: BANK an improved score. v1 = 5.60. v8 should beat it via: more hills, longer circuit, s-bends, banked turns (if they place). FASTEST PATH: v7 recipe minus loop kit (replace with 2 extra flats — NO ledger change since kit was net-zero... the kit occupied 9 tiles [flat,ftu25,u25,u25,loop,down25,down25,d25tF = 8 tiles + 1 flat]: replace with 9 flats → SAME downstream coordinates EXACTLY ✓✓ ZERO re-derivation!!) + sprinkle s_bends/banks in wide bands IF placements accept, else flats. Then immediate test. GO GO GO. Batch 1: station..loop-kit-substitute: [begin, middle, end, flat, flat, left_turn_5, flat, flat, chain ftu25, chain u25 ×5, u25tF, ftd25, down25 ×5, d25tF] = 22 pieces → cursor (51,83) ✓ (proven) Batch 2: [flat ×9] replacing kit → (50,92)?? 9 flats from (51,83) d1: y84..92 → cursor (50,92)?? wait d1 flats advance +y: (51,84)...(51,92) = 9 flats → cursor (51,92)!! DIFFERENT: kit ended at x50 because the loop shifted dx -1!! Without the loop the line stays x51. Downstream north-run column becomes x51 (not x50) — and NORTH RUN + hill occupy x51 y93-105: safe (nothing else there) ✓ but the EAST band corner start etc all UNCHANGED in y. And x51 column vs LIFT column x51 (y64-83)!! North-run x51 y84-105 continues the SAME column: (51,84) flat etc — adjacent to crest/floor tiles: … (5608 chars)

WAIT — cursor (89,113) d3?! Expected (88,104) d3. Let me recount: after batch 1, cursor (51,92). Batch 2 plan: flats ×12 → (51,104)?? I listed 12 flats → y93..104 → cursor (51,104); HILL 7 → (51,111)!! ✗✗ MISTAKE: v7's north run had [flats ×4, HILL, flats ×2] ending y105! Here I substituted 9 kit-flats ending y92, then added 12 MORE flats → y104, hill → 111, corner → (54,113)... band 33 → (86,113)?? Reported corner end (89,113)?? whatever — the band length I used: after right_turn_5 (54,113)... then flats: I listed 13+hill(7)+12 = 32 → 54+32 = 86 then corner → (88,110)... but reported (89,113) d3 — meaning my corner came after 35 tiles?? Counting my batch-2 array: 12 flats + 7 hill + 3 flats + right_turn_5 + 13 flats + 7 hill + 12 flats + right_turn_5 = 57 ✓ placed. Position math: (51,92) +12 → (51,104); hill → (51,111); 3 flats → (51,114); right_turn_5 δ(3,2) → (54,116)?!? reported says corner exit y113... hmm discrepancies suggest my tile-model of hill pieces is off (hills might consume fewer tiles?? e.g., up_25_to_flat counted differently). The ENGINE is ground truth: current cursor (89,113) d3 heading SOUTH, x89 ✓ SAFE (east of lake). y113 vs plan 104: 9 tiles "extra" — the whole east column now starts higher; it descends: corner target west-leg at y50: descent from 113 to 52 = 61 tiles (vs 52): BUT current cursor y113: descend to (89,52): 61 flats/hills: [flats ×16, HILL, flats ×16, HILL, flats ×16, HILL]?? 16×3+21 = 69 ✗: [flats ×14,HILL,flats ×14,HILL,flats ×12,HILL] = 61 ✓ → ends (89,52)... wait hills consume 7 tiles net each: 14+7+14+7+12+7 = 61 ✓ cursor y = 113-61 = 52 ✓ Then right_turn_5 δ(-3,-2) → (86,50) d0 ✓ (y50 SAFE south of lake) West leg: 42+2?? target corner-start (41,50): from x86: 86-41 = 45: [flats ×32, HILL, flats ×6] = 45 ✓ → (41,50) right_turn_5 δ(-2,3) → (39,53) d1; flats ×9 → (39,62); right_turn_5 → (42,64); flat → close. Collisions: none new (same perimeter, just 9 tiles longer column/leg). TIME: ~22min elapsed. HURRY.

Cursor (86,51) d0 — y51 not 50 (corner lands y51-2 = 49?). West leg target corner-start (41,51): from 86: 45 tiles: [flats ×32, HILL, flats ×6] = 45 → (41,51). right_turn_5 δ(-2,3) → (39,54) d1; flats ×8 → (39,62)?? 54→62 = 8 ✓; right_turn_5 → (42,64) ✓; flat → close.

STILL null with NO loops!! So loops were NOT the (only) culprit! v8 stats: inversions 0 ✓, drops 9 ✓ (sane!), air_time 14 ✓, max_speed 941155 (identical to v1!), lateral_g 1.29, negative -0.13, positive 2.26 — ALL PHYSICS SANE. ride_time 780 (timeout), ride_length 2148. So the difference vs v1 (which RATED fine): v1 = 90 pieces, ride_time 55. v8 = 206 pieces, ride_time 780 → the test ran the FULL TICK BUDGET without "finishing". What defines "tested"? Probably: the test completes when the train returns to station AND the game decides test done... v1's lap took 55s. v8's lap ~150-200s?? With 780s budget it could do 3-4 laps... why not rated? KEY HYPOTHESIS: default ticks = 25000 = 625 game-seconds; ride_time reported 780?? hmm 780 > 625. Whatever the budget, the test hits its cap. What if the test requires N laps or specific coverage and the TRAIN GETS SLOWER each lap (friction losses without lift re-engagement?? NO — the chain lift re-engages every lap...). ALTERNATIVE HYPOTHESIS: THE TEST TRAINS QUEUE: with a long circuit, the tester dispatches train #2 while #1 still running; they can't overtake; the test waits for ALL trains to complete; queue jams... OR: maybe rating requires the train to END its run INSIDE THE STATION with BRAKES?? Rules mention "brakes are for shedding speed before the station". v1 had NO brakes and rated fine though... DIFFERENCES v1 vs v8: - v1: 90 pieces, lap 55s, rated ✓ - v8: 206 pieces, timeout ✗ - v3/v5 (104-184 pieces): timeout ✗ MAYBE IT'S SIMPLY LENGTH: test ticks (25000) must cover the full test; longer circuits take longer per lap; with dispatch overhead (station wait times), a 206-piece lap might take 150+ s; the test protocol may need the train to complete + return-to-station + cool-down within budget → TIMEOUT for long circuits!! FIX: MORE TICKS! finish_and_test(ticks: 25000 default) — PASS A BIGGER TICK COUNT! e.g., 60000 or 100000!!! The parameter exists! v1 didn't need it; long circuits do!! TEST v8 with ticks=80000 RIGHT NOW — no rebuild needed!!

More ticks → ride_time 3592 (!!), still tested:false. The train rides for 3592 seconds and NEVER triggers "tested". So it's NOT a tick budget issue — the train keeps going indefinitely. It laps forever without the tester concluding. What ENDS the test? In RCT2 the test-run ends when the train completes the circuit and ARRIVES BACK AT THE STATION (a complete cycle). The vehicle must STOP at the station (station platform end). Our train returns to (44,64)... station tiles (44),(45),(46): the train ENTERS at (44,64) begin_station... but does it STOP? It needs to decelerate to a stop within the station platform. v1: lap 55s, train arrives, stops, test concludes ✓. v8: the train arrives at the station but perhaps DOESN'T STOP — overshoots?? WAIT — the closing connection: I placed extra flats approaching (43,64),(44,64): the track now OVERLAPS THE STATION?! Pieces 204-206: flat@(42,64), flat@(43,64), flat@(44,64)... "placed":"flat" at cursor 44,64 with circuit_closed TRUE — the final flat SAT ON... no wait it reported success placing flat with cursor→(44,64): the piece occupies (43,64)→ ends at node (44,64): adjacent to begin_station ✓ NOT overlapping. Hmm so why no stop... LOOK AT THE LIFT: chain lift re-engages... the train climbs the chain every lap; with 206 pieces the lap takes ~110-150s... 3592s = ~25+ laps!!! The tester NEVER stops it. In v1 (90 pieces, lap 55s): test stopped after ~1 lap. What if the TEST protocol = "run until the train returns to the station START NODE with the circuit flagged closed, then conclude"? The circuit node closure happened at the flat@(43,64) piece → node (44,64)... WAIT. Maybe the closure DIDN'T actually connect to the STATION but to my extra closing flat!! Sequence: ...flat@(42,64) [placed, cursor (43,64)], flat@(43,64) [cursor (44,64)], then ANOTHER flat "placed" with cursor→(44,64) reporting circuit_closed:true AND cost 600: that LAST flat... piece_placed occupies (43,64)?? cursor was (43,64) → placing flat: piece AT (43,64)?? NO WAIT — after the previous flat, cursor = (44,64)?? Let me re-trace: "...right_turn_5" batch ended cursor (42,64). place_piece flat → cursor (43,64) [piece at (42,64)]. place_piece flat → cursor (44,64) [piece at (43,64)] — should CLOSE here!! But it reported circuit_closed:FALSE. Then ANOTHER flat → reported cursor (44,64) & CLOSED with cost 600!! That third flat occupies... if cursor was (44,64) and it placed a flat successfully, the piece sits ON (44,64) = ON TOP OF begin_station?!! OR the flat went onto (43,64) OVERLAPPING?? It reported cursor (44,64) after... i.e., piece placed AT (43,64)... but (43,64) already had one!!! Hmm OR the closing mechanic: placing a piece whose EXIT NODE = station entry node = closure, piece rendered on (43,64)... In v1 the EXACT same thing happened: extra flat at cursor (43,64)→ closed:true, cursor (44,64), cost 600. v1 rated fine. So closing mechanic identical... ✓ NOT the issue. THINK DIFFERENTLY. What ACTUALLY differs v1 → v8?? 1. Length 90 → 206. 2. Station: identical. 3. v1's lift fed DIRECTLY from end_station (uphill right after station): same in v8 ✓. 4. TRACK SELF-PROXIMITY: v8's south leg runs y51-54 through x39-86, east column x89, north band y107-116: no near-misses... WAIT!!! ride_time 3592 with ride_length 2875?? v8-first-test: length 2148 @ time 780; second: length 2875 @ 3592. The length grew with more ticks = train kept accumulating distance = MULTIPLE LAPS: length = cumulative distance!! v1: length 474 @ time 55 — single-ish lap. So YES: train laps forever; the test ends only at... maybe when the train's SPEED at station-arrival < threshold (so it "parks")? With a 96-drop and big circuit, the train arrives at the station at HIGH SPEED and blows THROUGH the station without stopping!!! v1's train arrived slower (shorter lap = less residual energy?? no — same energy...). Hmm, v1's circuit had MORE friction relative to drop? Actually v1 lap 55s... RCT2 station-arrival: trains ALWAYS stop at station end-block … (5859 chars)

Ride is finalized/locked after finish_and_test. Full rebuild needed. ~25 minutes elapsed. FAST REBUILD of v8 with two changes: 1. brakes (speed 8) ×2 on the final approach before station 2. That's it — keep everything else identical (206-piece v8 sequence). The v8 sequence from placed_pieces log (206 pieces). Rebuild in 4-5 big batches, replacing the last 3 flats with [brakes8, brakes8, flat] + closing flat. Wait, also consider: maybe better to make this build slightly SHORTER to also test the "length" theory? NO — brakes theory is stronger (v1 stopped fine; only long-circuit builds failed... hmm v1 short AND stopped... correlation confounded). Add brakes anyway (zero risk), and if still null, the next iteration shortens the circuit. Actually — time is short (~25 min in). Also reduce lap length modestly in the same pass: trim the east column descent by turning at y~78?? NO — collision-safe perimeter requires full descent. Keep length; rely on brakes. Execute: new_ride + 5 batches with final brakes.