I can run two at a time here (Kanotix 2005-03 but I don't think that matters). Can you try running them from command lines like:
Code:
~/.zAppRun /home/rayb/Desktop/lsongs.cmg
and see what errors you get? You could try to look at /mnt/app to see what's happening in there? I can't really tell anything from your description. Are you sure your fstab is right?