Looks like each train car is rotating around its center, causing the front and rear ends to leave the tracks when turning. You’ll want to sample two points on the track, one at each end of each train car where the wheels would be, then use the two points to position the car more correctly.
If you look at extra content surrounding the original, it becomes pretty clear that BGE2 is what they always wanted BGE to be in terms of scope and theme, but after so long in development now, I can’t help but wonder if the restrictions on scope were what made the original truly great.
I hope they manage to pull it together into a cohesive product eventually-- and I will be playing it when they do-- but I would be truly surprised if the sequel is as impactful or memorable as the OG