Quote - I saved the files in Pro. I'll check UAC. No I am not saving in the defaul folder, does that matter?

If your scene has items from multiple runtimes, pro may be having a hard time finding files as the pz3 was saved with relative paths. UAC restricts write privileges in your Program Files folder, and can therefore cause errors if the application does not account for this. If you aren't trying to save scene files there then it's not a problem.