So here's the first "Omega Man" or "Sole Survivor" (or whatev) map. Zombieland Classic is running it now. The gameplay rules are printed to the console when you join, but the basics is that the blue team needs to have one player and that player will be the "omega man". To start the round the blue player needs to /kill. The round ends when one of the Zombies (red players) kills him, at which point the killer starts the next round as the Omega Man. (Both teams have unlimited spawns otherwise.)
http://www.gamefront.com/files/20738901/om_base1a.pk3
Size: 5mb
Zombieland admins: The server is currently set to Omega Man mode with g_esmzombie set to "2". To change it to normal Zombies, set g_esmzombie to "1".
Let me know how to improve this if you care.
P.S. Guard, you srsly gotta fix the captcha on this site. I log in so infrequently that I keep forgetting my password and have to constantly reset it using email validation which takes forever.