Ok, now I am baffled
I've been under an impression that IL-2 just changed the encryption keys and that's why original unGTP tool couldn't decrypt files, but I've never looked into contents of gtp files.
So I did take a look now... and well... it was easier than I expected.
I assume this means it is ok to make a new version of unGTP.
Edited 4 minutes ago by AnKor