I'm sorry to say, that is basically an impossibility.

Firstly, since Desura is gone, I no longer have access to any list of people who actually purchased the game to verify for key distribution. They never paid me anyway, so you can probably guess I'm none to happy with that situation.

Secondly, this version of the game is much expanded from the game that came out back then. I put in a whole lot of effort to not only update it for Steam as a platform with new online leaderboard capability and stat tracking, but spent the time to add an entire new character with new mechanics and a separate story line. This new version also drops the defunct XNA platform in favor of the modern FNA replacement which runs on OpenGL instead of DirectX. There's also expanded support for controllers and a host of other improvements.

Thanks for putting it in another bundle. I'm hoping Groupees paid you. I purchased that bundle primarily for this game and enjoy it even though I suck at it,

Its a shame what happened at Desura. I purchased a lot of bundles from them. I've heard of other devs/publishers getting screwed by them.