You do realise that this is a keychanger for the first ArmA game, right?
And Z, you guys packed the newest (if you can say that, it's a tad dated now) one with some unknown packer. So he won't be able to jump past the validity check like with the last ones unless he unpacks it first.
But the hashing scheme from key ---> registry looks about the same for both, so you're on the right track.