Just finished playing co-op with one of my best pals (because I'm too much of a pussy to do it on my own
), and the only bugs we encountered were first off, a sawer went through a wall (with a door next to it though), and for the rest a few lighting errors, for instance a blue tree, or a bright model between lots of darker ones. I'm glad it finally got a steam release, now more people can join in, and most likely there will be more custom maps and maybe even 24/7 servers now. I hated these guys alot though:
