Adding a Returns Module to Northwind 2007

[cw via AccessMonster.com]

I have decided to look over the Northwind 2007 database and see if it is
adaptable to real use. (Note: I searched and searched for weeks but have yet
to find a single document or resource that walks you thru the logic behind
NW2007 database, for ex.."How to use it as is? or How to Adapt it to allow a
return Transaction?) Anyone know of any books or resources on NW2007?

Anyway, I have conquered the beast and adapted for a friend to use as an
Asset, Inventory & Ordering database.
Here is the question I have: How to add a Product Return function?
- The Company places a Purchase Order for 20 widgets
- The Inventory is Received and available for Customer Orders
- Customer Order is placed for 5 widgets
- Later, Customer needs to Return the 5 widgets

Here are my thoughts on Returns:
- Just place another Order for that customer, and make the Qty = -5 (that's
negative 5)
- This would allow the Order History Tab to reflect each transaction..?
(ordered 5, returned 5)
- Will this work to "put the Inventory back in Stock?"

Any ideas or anyone familiar with NW2007 would be much appreciated..
Sorry if I have overlooked something in NW itself..
Thanks,
cw