Hi J. , well that's the specific error that you'll get if it's run from the Downloads folder and isn't moved over to /Applications. Can you please ask them to double check the the actual MoI 3.1.app bundle has been moved over and they haven't done something like just made an alias to it?

It shouldn't normally need any permissions editing, although maybe that's possible if they have downloaded it on one computer or user account and then are running it on a different one. They may need to take ownership of the app in order for it to be able to write to its own Info.plist file. If possible ask them to download it from the same machine and user account where they intend to run it.

- Michael