I have removed the REGISTER parameter from the Start menu shortcut.
So, the method for installing an updated release is to download the latest file of the product and re-run the installation. When prompted, a new repository is not created. The app can be launched at the end of the installation and I am not prompted for the registration code. If I then close the app and attempt to launch it from the Start menu shortcut I find that the REGISTER startup parameter has been reapplied. With each upgrade installation I should clean my shortcuts or there is a step I have not followed correctly?