Unfortunately I can't refund the Pro version any more im Google Play, as the refund period is over. I read about the licence key from the website when I get problems with the registration. So would it be possible to refund my purchase by you afterwards and send me a licence file instead? If not, I just have to bite the bullet and buy the license again on the website. In any case, I prefer to be independent on the Internet all the time, even if I delete my data.
I will contact the support and see what they can do for me.