A line-following driver stalls or wedges at the same place every lap

Symptoms

A driver that steers along a recorded racing line runs well, then turns into a wall at one spot and stays there; its log shows the line index stuck near the line's last point.

Cause

The line was recorded for a fixed time shorter than a lap. At its end the next aim point is the line's start, far across the level (observed: a 60 s recording on POD's Alderon, where a lap takes about 70 s).

What to do

Record more than a lap from a computer car and cut it where the car comes back within a few units of its first point, so the line is a closed loop: ./gameframe run loopcut REC.jsonl --x car_x --y car_y --index 1 --out LINE.jsonl. Check the gap between the last and first points before using a line.