That's what I do to race, and win and don't get any bug.
Save before trying.
1> Never run the test course.
2> Press jump key before green light (seems to correct the swoop bugged starting position).
3> Reload if hit a wall or mine (seems to correct one of the too unfinished race message).
4> Try to hit finish line in the center/right (seems to correct one of the two wrong race message; maybe the invisible line is misplaced on the left and won't let you go as far as u must when u finish a race).
5> Never "forfeit" a race.
It works for me ^_^