I had a old version of the gog game installed with only chapter 3 (I think it was 3..). I played it and finished the chapter today and it worked fine.
Then I tried to download the rest of the chapters. I went to gog and downloaded the new download files of the game (and the newest patch there were). I tried to do the setup with the newest version of the game. I made a copy of the save files in case something went wrong. The space required to download the newest version was so big (over 20 GB) that I had to download it in G: instead of C: where the old version was.
I copied the old files to G and I downoaded the new version of the game in G: (and there was some error notification in the middle of the setup, something like "file xx can only be read, do you want to try again or skip?" I first clicked try again and it didnt work so I clicked skip.). After the setup was finished I tried to start the game. It didnt start. It just opend a window that said
"Oops! The game crashed. The crash report folder named "2017-04-02_011930" next to game executable. It would be great if you'd send it to the developer of the game!" "(OK)"
I tried to run the newest pach 2.15.0.22 but it didnt work
"This pach does not support your version of the game. Please download a new installer"
Then I thought everything was too messed up. I uninstalled the whole game.
After that I installed the game again from the newest setup files version from gog. All the same things happened once again and with all the same error messages! I dont know what to do now. This has taken almost the whole day... I would like to play chapter 4...
Thank you for your help