Normally upgrades are supposed to work, in this case it has been nothing but a failure. I have logged a support call and so far nothing. And yes I paid for the Extension.
I'm sorry you've run into some troubles. I've looked through our open support tickets and can't find a thread similar to the bug you've described. Please drop us a line directly and we'll either send you an immediate refund or (if you prefer) solve the issue you are experiencing.