Hi,
I would like to install a MOD on my IL2 but to do that I need the original 4.07 version. There is a way to downgrade the game to 4.07??

Thank you in advance!

I don't think it's possible. I haven't installed the gog version yet since I only bought it recently but it's clear from the file size that the installed game is not stock. In my opinion, gog should have included vanilla as an installer, and then a mega-patch for patching 4.07 - 4.12.2 since many mods depend on older versions.

It's up to the gog guys to include a 4.07 installer and a mega patch for 4.12.2. It shouldn't be a problem since such things already exist in the IL community.