I never had a go kart getting stuck at the edge of the track but I run into the problem of go karts not fitting into the station. This happens to me with every fricking track no matter if it was custom built ore an official one. It is always the same: I built or buy a pre-built track, open it, have fun looking at it, get's stuck at the end of the race because instead of driving into the start formation the karts just stack behind each other and stay this way. I've tried many different things to fix this, for example making the station longer, using less karts, using different types of karts ect., but nothing solved the problem for me. I really hope for a solution of this problem, because this makes building go kart tracks, one of the most fun things in the game in my opinion, pretty much useless because they just pay out once and then get stuck. This really sucks.