I got it! I used the steam key.
Installed Trine and it only brings me to the "Trine Launcher" and when i press the Launch button my steam avatar goes back to blue from green and nothing happens, Is there anything i need to do so that Trine will work.
P.S the shadowgrounds games work.
Ah, so that's why I got 837 popups of you playing Trine.
Hehe, Sorry about that D;
Im now in the tech chat at there website, One of the developers of the game is helping me :I
So im guessing it will end soon