OK, that is not a problem in EU where software are 99,99% impossible to register. Anyways, a patent applies to an invention. A nag screen would not arguably be

OK, that is not a problem in EU where software are 99,99% impossible to register. Anyways, a patent applies to an invention. A nag screen would not arguably be the object of the patents for that tool since it wouldn't be their own distinct invention. You can only patent novelties. You've done well.