I tried to enter a uberent 4-person game. Everyone left, I was the only one remaining (hit "ready" guys!) and then the same started. However, it was "starting game" for around five minutes so I hit backspace to get out of it. Then the game went to "log into server rejected", returning to menu, or something like that. Then the game froze and I had to force quit. I'm running this on a Mac OS X 10.7.5 through steam.
There was new version released just right now: https://forums.uberent.com/posts/797909/ From my experience this might be related, after all devs need to update game servers somehow too.