After making your donation, I will process your request within the day and you will receive an email allowing you to deactivate the donation reminder popup and access certain additional features in the ARRM application.
The email you received contains a .zip file of the type user_test@servermailtest.com_thanks_for_ARRM_donation.zip containing your registration key.
If you have correctly registered your key, after launching ARRM, you should see Registred version in the application title banner
However, on some versions of Windows, this procedure does not work.
See below how to do this manually:
If you have correctly registered your key, after launching ARRM, you should see Registred version in the application title banner