I have no clue how to fix this problem, the maps that have the UGX start screen or whatever it is called ie: Zombie office/battlestar galactica have no option to change the map/gamemode. whenever you attempt to start a game with friends, the game attempts to load "semper fi" the campaign mission on the Nazi zombies gametype, this does not exist, so anyone in the lobby crashes...  does anyone have a solution to this problem? thanks