Actaully, I think there's one more thing you could fix here. After that turn-around, where the track is going diagnol, I noticed that you made the track go up 5 ft, causing it to straighten out then go back into the turn. In real life that manuever would probably be fatal, so if your're going for realism I think this will really help: delete all the flat part of the turnaround and instead of making it wide and going up when its diagnol, make a half of a helix going up, then make the diagnol part but now it will already be raised 5ft so you wouldnt have to put that jerky section and it will flow smoothly.... but that's just my suggestion.