clarry: Offline installers are supposed to be generated automagically from the same files that make up the galaxy installation. There's no good reason why it should be a major burden for GOG staff.
https://docs.gog.com/offline-installers/
I kept hearing rumors that they are, or a least could be, automatically generated, but nice to see some official source for it.
Still a few questions spring to mind (not sure if you know the answers, but just stating them):
1. Are the game installer names and version numbering also automatically generated, or does a human have to supply them to the system? I have no idea if the Galaxy versions of GOG games have similar version numbering that the offline installers could just use.
2. Some installers have separate patches, some don't. How does the automated system decide whether separate patches are generated, or are they generated automatically at all?
3. Does the automated system generate separate language versions, or does it do it the Cyberpunk way, packing all different language versions into one biiiig installer? Or does it support both ways and the developer just has to decide which way to go?
4. If the whole process is automated, why are there still sometimes quite long (days, weeks?) delays before the offline installers are updated, compared to the Galaxy versions?