Sorry for the "necrobump", but does this game require phoning home to the developers in order to host a game? I tried hosting a game for some bros, and it froze, saying this in the logs:
>ERROR: Failed to contact rendezvous server (relay.kartkrew.org).
Apparently I accidentally broke the DNS on my Linux system some time before launching the game, and I promptly fixed the DNS issue (it wasn't able to resolve any domains, not just the "kartkrew" one), and that also fixed the issue with the game and I was able to host the game fine.
But what I want to say is that I still think it's concerning that you apparently can't host a game without connecting to this "kartkrew" server.