Guys, if you pick the Boxmaster + Mills track, you're not able to pit out. You basically knock your head into the top of the garage. There's only one lame way you can make it. You have to reverse back, get some time and momentum and force it through with a crash.
You can't fit all rF2 cars in a kart track garage either. I think this is more a limitation of the track than a bug. The only solution would be to re-build the entire garage building, which surely won't happen.