I was wondering if there was a way to connect to your own computer to connect to your own server offline (using online connection button) to play custom modes like zombies.

Meaning like what Norwegian Elite Wotlk Repack 6.0 for v 3.3.5a did. You could connect to your own computer on WOW but play offline (for those who don't have internet regularly).

I found a zombies mode that looked pretty awesome for MW2 Don't know what it's called and I'm not even sure if there are any zombie mods on MPGH. I was looking and couldn't find any...

Just wondering if someone could point me in the direction of where I need to go to learn how to code a game mode? And also how to connect to yourself by setting up a server and connecting.