I, like many many others have had a miserable experience with this broken piece of junk that masquerades as a legitimate, premium plugin (I bought the dreaded "Gold Cart".
Over a period of several weeks I floundered through every step of the process with this product - from purchase to installation to activating the store. I never got it to work and the support information is totally inadequate. I would say people should avoid this nightmare and get something that works like it is supposed to. If you don't believe how bad this thing is, just Google WP ecommerce reviews and get ready for an avalanche of frustration like I've described.