Our guide to port forwarding may help here. Before proceeding, ensure that UDP port 2342 is open on all players' routers and/or firewall. Whichever multiplayer option you take, one computer must act as the server to host the game. However, simplicity (and trouble-free play) dictates that all Deathmatch players should be running Chocolate Doom, and the same WAD file, before starting. Internet and local network play are both possible with Chocolate Doom.
