Is it possible to swap my copy of the game from gog to steam? I didnt add it on gog yet.

No - as far as I know if you want the "Steam" version, you have to buy it on Steam.

You can add the game to your Steam list/client but only as an 3-th party game, and not as an Steam game.

Damn. I have my copy from a draw.
Thanks anyway.

Well - I also have my game here on GOG, nothing wrong with that.

But - If you really wanted to have it on Steam, you could try to sell the game to somebody else (as long as you did not used the key yet), and use that money to buy it on Steam...

I have all my games on steam so i wanted to have this one to be on it too. Also this copy is with signatures of the creators so i dont want to sell it and i dont know anyone trustworthy who want to swap it with me.

Edit: I mean swap only codes, not whole boxes with cd-s.

I am starting to regret getting current games on GoG because they are so much slower to get updates out than steam.

GOG is a company of this game's creators, so I really can't see how they are slower than Steam on this one...