If you join the sparqueue, the count says one. That's allright, but if you then leave the room without resigning the count of 1 will stay for may be 1-3 seconds. And if a second player joins the queue then, you have to spar him.. the funny part is you already left the room. So your loading of your map will fail, the result is: you get stuck in some black walls on the lefthand corner at the top, and you lose a spar without even trying. The other will win that spar, of course.

Sometimes, you just forget to resign from the queue before you leave the spar room, and then this happens.. -_- Should of add some function which says "the other player is not in the room anymore!" and count it as a tie, since I don't think there is a way to evade that since it's caused by lags merely. Or, you add some "You can't leave the room untill you resign from the queue!", that would be nice, too.
This doesn't happen a lot, but some people try to get wins on this way, and it happend to me twice already, eh.