Alexim: I don't know what Ganni1987 means, but the many extra achievements of Surviving Mars added on Steam with the latest updates/DLC are missing on GOG.
JudasIscariot: Can you tell me more about which achievements are missing? The more info we get about this, the better the chance that it gets resolved quickly :)
Sure: Surviving Mars on GOG Galaxy has 50 achievement, on Steam 60.
They added 10 new achievements only on Steam with the Gagarin Update as you can see here:
https://steamcommunity.com/games/464920/announcements/detail/2484194130755271976 Space Shopping - Play as USA and have a Geoscape Dome with a Megamall before Sol 100
Tao - Play as China and have Tai-chi Gardens in 10 Domes before Sol 100
Space Capitalism - Play as Blue Sun Corporation and produce $100,000 M Funding before Sol 100
Europa Universalis - Play as Europe and reach daily production of 10,000 Research before Sol 100
Waste Not, Want Not - Play as India and convert 3000 Waste Rock to useful materials before Sol 100
The Pace of Progress - Play as SpaceY and complete all Sponsor Goals on challenge rating 500% or higher
No Pain, No Gain - Play as Russia and have 500 colonists on challenge rating 500% or higher
The Garden of Eden - Play as Church of the new Ark and have 250 Colonists at 70+ Comfort before Sol 100
Bushido - Play as Japan and train 200 specialists before Sol 100
Gold Rush - Play as Brazil and convert 2000 Waste Rock to Rare Metals before Sol 100