[Arralen]

Internal IPs are most likely in the 192.168.x.y range. Start a command line window and type "ipconfig /all". You'll find a LAN ethernet card listed with IP given.

1 PC has to be set up as "host", though one player might play on this machine, too. You'll have to start 2 instances of Dom3 on this machine. The instance which runs as host does not need a seperate KEY - only the player (clients) need one each.

For hosting, make a seperate shortcut with the following command line options:
PATH\dom3.exe -fsmw --tcpserver --res 800 600 --port 4000 --noclientstart

This will start up Dom3 in a small window, without sound and music, and will take you directly to the "enter game name" screen (hint: if you want to continue an old game, just use its name). After you entered the game name, the server is waiting to accept connections from the clients. On top of the window it will show the local ip and the port its running on (set to 4000 by the command line switch).

Now start up Dom3 on the different players PCs and chose "network game, connect to server", type in the IP and port number given by the server.
If you're playing on the same comp the server runs on, use "127.0.0.1" for the IP, or "localhost" if that doesn't work.

When all players are connected, hit "start game" on the small server screen.