I'll give that a try. I'm just hoping that there isn't some fundamental problem with an ad-hoc network for LAN play.

Yep, we're on 0.13.1+, so one of the methods we've tried is Play over LAN. We can see the game but can't join.

I have been trying for a while to play co-op with my college roommate.

First we tried LAN play, but that didn't work. Then we tried internet play but that didn't work either---I was able to join public games but not my roommate's game, even though I could see it. I suspect this has to do with my ...