You would do this type of functionality something like a "splash" screen that's mentioned in the Dev Guide such that if the user returns to the 'Home' page, one condition of home initialization is that a full-page widget is displayed that asks them to enter a code.

This whole solution hinges on the 'System.setGlobal()' functionality that will be erased with a firmware update or with a reset of the remote. Therefore, to do a solution like this, you will likely want TCP connectivity as SWORDS mentions and you might want to build "pronto licensing" per se into one of your public websites. Each config you develop gets a key and in order to access, you must hit the licensing website. If licensing passes, then home page can be made active. If not, then pop up the full page widget asking to contact the vendor.