Sorry, I was just browsing through here and saw my response was cut off...
Ebay API handles cancellations differently than returns. Cancellations stop getting sent through the API after the cancellation, and a return keeps being sent, but with the refund information added. So if you cancel a transaction, there is no signal to tell the program to refund the sale, you would need to either add a refund or delete that transaction row manually. I hope that helps.
