And as far as I know it's up to you which car you pick although I see your point and it might be an idea to assign cars to entries. Although it may now be a bit of un-necessary work for the organisers and won't really detract from the actual racing if not.
Just jumped on server to see if all is ok, and seems so although
... I had some dx track map plug-in installed but got booted as possible cheat, so if you get issues and have that installed - ditch it and you should be OK.