So, I'm playing a game with a friend, but his computer sucks and crashes every now and again, when it crashes it leaves behind a clone, and if I understand correctly to save the game you need to have only one player logged in, but I'm pretty sure the clones make it impossible, is there a way to kick them from the game, so that I can save it?

I think fixing your friend's garbage computer that can't run a 14-year-old game without crashing will be easier than finding a workaround to your problem.

Probably ^_^
I was really bored that day though.