The game's system requirements don't list Windows 10, does it function correctly with Windows 10 or not?

Also I own this game on Steam, however it doesn't allow me to play (YuPlay related?) does this use the YuPlay client?

Thanks.

Yes this works in Windows 10; however, I had to install the game to the C drive (can be in the root or C:\Games). Installing on any other drive and it wouldn't load the Missions or Encyclopedia - same issue with Steam version.

This GOG version doesn't require the YuPlay client to run - but is single player only.