Episode Selection and 3 or more player Help

[VGF24]

I just recently installed the latest version of GZDoom (3.4.1) and was able to play Co-op with one of my friends via .bat documents. I was able to play normal vanilla Ultimate Doom but was unable to select which episode we would play. Also getting 2 player Multiplayer to work was easy, but I have no idea how to start a 3 or more player Co-op match. If someone could help me with these two problems it would be a big help.