I think that if you purchased after feb 06, you get the v2 upgrade free, according to the link below...check it out
http://line6.com/rifftracker/version20.htmlas far as using RW on 2 computers, I think that you need to have the guitarport hooked up to whichever computer you are trying to launch it on, I think the hw acts as a dongle for the sw....
I just got a ux1 this afternoon, so I'm by no means an expert, but I saw something in the gearbox manual about transferring authorizations, i.e. 1 license on > 1 computer...
maybe one of the moderators can give you a definitive answer?
Otherwise, check the pdf that comes with gearbox...hth