ZSNES board

Is it a faulty dump of the game? I mean, I'm guessing by the sounds of it you've checked the entire checksum and whatnot. Have a look at getting another dump of the image and see if it makes any difference.

Why would unchecking UDP help on a LAN? I'd like the techy explanation really, to be honest

He's just referring to the typo of the original poster (Apologises for obvious statement) Anyway, just as everyone else will pretty much say, check the documentation and don't expect more than 2 players over netplay on ZSnes as it's strictly 2 players (via netplay connections) only right now due to ...