Thanks, it could just be my computer but i've never seen a game do that
Very low/high framerates can do all sorts of strange things in games, it's just a bit more obvious here.
If you're interested: The way the train works is that it gradually builds a path to follow as it moves. Every frame, it checks if it needs to build a little bit more of the path. (A gif from early in development showing this process)
When the framerate is really low, this checking doesn't happen often enough and the train basically moves faster than it is building the path, so it glitches out.
It's just a visual thing and should fix itself when the framerate goes back to 15+. I've also fixed it properly for the next version.