Anybody can make an iso image and share the registration code or password the z110bt is not going to comunicate with any headquarter online and let them know the same software has been use by more than a person.
You have to receive a unique password from Pioneer to your upgrade to enter in on the unit or you will not be able to install the upgrade to your unit. That password will only work for your unit. Its not going to be as easy as just copying the image from the SD cards.
I can't imagine they would make it easy to do this when its become so well understood that everything finds its way onto the internet.