Using backed up Witcher game from GOG

So I figured I can install GOG galaxy to keep the Witcher game updated and the saves too. I then added a separate game for the Witcher 3 Wild Hunt and applied the GOG galaxy Witcher 3 installer settings and same prefix /home/$USER/Games/gog-galaxy

The game ran fine but I didn’t enter the game, all my saves were there and I guess I just need to run GOG galaxy after I play to upload to the cloud. Now I wonder if I can make an installer with this purpose so I don’t have to input all the variables and settings of each game. I will do anyways but maybe I can help users migrating from Windows to set it up the Lutris way.

The installer will use no setup files since the game is backed up but maybe it can copy the files from the external HDD but maybe that is a step that can be done manually after installing GOG Galaxy. The only functionality I am thinking of is using custom settings for each game in the GOG Galaxy prefix.