Thanks for the followup. I am more than a little concerned about your bug report and that you seem to have found other experiencing the same problem. Do you mind letting me know if you were using the payment gateway “Test Gateway” or some other one?
I just tried running the latest version of WPEC, WP, Events Calendar, and Events Calendar PRO. I added a ticket to my cart and succesfully purchased it while in a browser had never logged into the site. Then I logged in as a subscriber. I was able to purchase and check out fine. It seems I am wholly unable to reproduce these problems. If you can offer any more details I will continue to dive in, but if you would rather spend your time look at alternate Ecommerce solutions I would not blame you.
Thanks for reporting this. If there is anything I can do let me know. Cheers!
– Brook