Nevermind seems like because I name two bones: bip_shoulderBlade_R and bip_shoulderBlade_L, it was causeing the error. Did I mention I have no idea what I'm doing?
Anyway I renamed them back to their original title and works fine.

I seem to be getting the same error: http://i.imgur.com/zUiCJh9.png
However, I'm using the source tools 2.4.1 (and blender 2,73a).