Many, hopefully most of these Steam crashes on startup will be solved in the first update (due sometime next week). This is most likely caused by a conflict between the Steam copy protection and the way vorpX ‘hooks’ into games. The strange thing is that it affects different games on different machines. Some don’t have it at all, others can’t start multiple games. Pretty nasty issue, but who knows exactly what Steam does…
I’m quite confident though that the coming update solves this in most, if not all cases.