It seems my new little world I created on the PC in the lab at school will not run on my Mac. It is a world where I have a nerd passing a can of pop around the room and singing, 99 cans of pop on the wall, take one down and pass it around ... you know the rest ... as it loops around and around till there are no cans of pop left. As soon as I open the file on my Mac I get an error message over and over again until I force quit. Works great on the PC