Unzip all the pk4 files into your doom3\mcs folder.
Host creates a dedicated cooperative server under MCS by choosing any other sample map included in the MCS. Once the dedicated server is up and running, go under console and type "si_map e1m1" (without quotes) and press enter. Then type "serverMapRestart" (again, without quotes) and press enter.
Clients can now join the game. Just be aware there is only one spawn spot for each player. Once a player joins, the player should move quickly out of the spawn spot to enable other players to join.
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