I hate to ask this here but im not sure where else id ask. Have you already sent backers steam keys and I missed it, or has it yet to be done?
Go here http://www.uberent.com/pa/ Sign into your account, and click on My Keys. From there you can convert the uber key over to steam.
I converted 1 of my 2 keys key to a Steam key without hassle - I bought the second key for my wife but now I'm not sure how best to send it to her. It says just send her the code and she can activate it via her Uber account. When she logs into her Uber account it asks for a code and there is a big 'activate' button - but if we intend to play through Steam do I still send her the Activation Key and activate it through her Uber account or do I just convert it myself from my account and send her the Steam key? Cheers.
This game works though own network backend called UberNet. So it's doesn't mater where you bought/activate/download the game you still able to play with everyone else.
If you both want to use Steam anyway just convert it to Steam and send key. I not sure if gifted UberNet keys can be converted or not.