You can copy the "Multi-User prefs" and "Multi-User Item" or whatever they're called from the Preferences folder in the System Folder to copy the settings; the "items" is a folder, the "prefs" is a file.
As for your other problem, I'd try trashing the prefs and resetting it under a new account. Or just create a new one, set it, if it works, delete the old one.
Are you sure that while giving permission to open the app, you haven't set an overriding option that would forbid its execution?
[ 10-19-2001: Message edited by: Cipher13 ]