Maybe you can print the ticket for customer. You can create special formatting for custom created order states. Check this document for the idea.
http://www.sambapos.org/docs/doku.php/en/v3/creating_printer_templates (Sorry for the poor documentation. We'll have more after bringing features to latest state)
Hint: I don't know if you noticed or not but you can setup individual account transactions for states. For example: Create a new account called "Returns" as the same type of "Sales" account. Additionally duplicate "Sales Transaction" type, call it "Return Transaction" and inverse account templates. Choose "Returns" instead of "Sales" account and keep the other one as "Receivables". Finally choose this transaction type for "Return State".
Now when you setup the default account screen for displaying "Returns" account you can display Return transactions total & details separately. That trick was something I was trying to achieve for months