I'm terribly sorry, SouthProArt, but the reason it's failing is that our Checkout does not currently support ProPay as a payment method. Starting on Monday it will fail "more gracefully", however. That is: the buyer will be able to select shipping, insurance, etc., and the transaction will be marked as "complete", but the actual payment will need to be made separately. I do not know how eBay's relationship with ProPay works, e.g. whether it's supposed to take place of our third-party Checkout system or what. What did ProPay say about it exactly?