[hitaisin]

gog version doesn't have cd-key

[*Tommy*]

You can add any game you have to the Steam>library although you cannot redeem it through Steam for achievements if that`s what you trying to do .
To add a non steam game to the Steam Library
1) Open Steam
2) Click the games tab (upper left of Steam window)
3) Click add a non-steam game to My Library
4) Scroll through the list and make your game selections
5) Click add program selections

[hitaisin]

ok, I bought it second time , just for collection.
I hope in future I can play witcher games on ubuntu...

[On2wheels]

Although it would be very cool if we could add our gog versions to Steam for achievments!

[Demut]

Send your complaints regarding this Steam’s way since they’re the ones who are not willing to do so.