I am trying to play a game with one friend online and a friend at home. I try to sign in as a guest under my account and the option is not available. I'm in the game lobby and there is no option to join the game. I have tried signing in every way possible there is. I just want to play Left 4 dead with some friends. I don't need this to be complicated. And I believe that it is a lot less complicated than I'm making it.