Right, so, I made a simpler layout with 3 checkpoints and a finish, with an insim split over each one. I've added the replay and the layout if it's needed. I did two laps, and the log is below.
The good news is that the gap looks consistent

That was my big worry from earlier in the thread.
(The first UCO time is the time it takes from /restart to green lights + reactions + inertia)
UCO: Time = 9.31
UCO: Time = 12.10
SPX: STime = 04.11, ETime = 04.11
UCO: Time = 15.14
SPX: STime = 07.15, ETime = 07.15
SPX: STime = 10.56, ETime = 10.56
UCO: Time = 18.56
LAP: LTime = 13.27, ETime = 13.27
UCO: Time = 21.27
SPX: STime = 02.38, ETime = 15.65
UCO: Time = 23.65
UCO: Time = 26.95
SPX: STime = 05.69, ETime = 18.96
SPX: STime = 08.49, ETime = 21.76
UCO: Time = 29.76
LAP: LTime = 11.06, ETime = 24.33
UCO: Time = 32.33