1) Can you select what character you want to play as? If so, how does that work? Yes you press a number listed beside a cahracter name.
2) Can you use doors, lifts, and teleports in multiplayer? No exept for doors, I just discovered this but even thought the are statick the still work.
3) Are you able to play MP3s or other music formats in a multiplayer map? With tweaking yes.
4) Are you able to chat in the game? Press "t"
5) Are you able to add more than one map? No not in the game builder but with somthing external like multimap you can group them together.
If you want more detail please ask. I would *not* recommend FPSC for it's multiplayer though.*
Slayer_2