Sometimes I am an old dumb idiot wink

The problem was a very simple one:
- The backup key file was corrupt. I just noticed that I had another backup of it and then I realized that the other one that I tried to use to unlock the GStudio7 installation was 0 KB in file size. Which is totaly wrong wink
Now the key file is recognized.

Thanks for the help guys, and sorry that it was such a stupid mistake!