Sales Return Order vs Credit Memo

Hi.

I have read the NAV documentation/help, and have read quite a few threads on this forum, but I'm still missing something about Sales Return orders.

When I created a Credit Memo for an item and posted it, on the Posted Sales Credit Memo (navigate) the inventory was debited, and the cost of goods was credited. No problemo.

When I created a Sales Return Order for the same item and then posted it, there was no change to inventory and cost of goods on the resulting Posted Sales Credit Memo.

Wondering why, I created new examples and before I posted them I examined the Sales Lines. The difference was the 'Return Qty to Receive' on the Sales Return Order line was zero, but was non-zero on the sales line in the Credit Memo (It was automatically set to the Quantity I entered.) If I fill in that value on the Return order and post it, the inventory IS adjusted as expected/desired.

So, here is the question: Since it is possible to post a Return Order where the 'Return Qty to Receive' is zero (or, at least not equal to the quantity), there must be another step in the Sales Return Order process whereby the inventory and cost of goods are adjusted. Whatever it is, the documentation is 'light'.

Thanks in advance fo any light you can shed.