If a customer come in and does a return and needs to get a check back you cannot tender the return as check. It messes up accounting since you cannot write checks out of RPro. So, here's the best method:
1) Tender the Return as Store Credit
2) Write check out of accounting allocated against Store Credit Adjustments
3) Edit the customer Record to reduce the available Store Credit by the amount of the check written.
This offers the best audit trail between RPro and Accounting to track the return and the check issued.