Okay, first, your PoFV .exe needs to be named th09e for adonise to work. So if you use vsync with PoFV, you might get annoyed.
Anyway, the server option is to host. Client is to connect to a host. Watch is to connect to a match in play.
When it asks for the port in server or client, you just need to use the same port as the host. The host will need to have this port forwarded/opened in some manner, or you'll have to use hamachi.
When it asks for IP when you select client, enter the host's IP (have him/her use whatismyip.com if they don't know it)