Okay.... I've got another question. In the 'full details' on the cart, I changed the description to show the SKU (a field I added after creating the cart) rather than the product ID number. Initially it displays correctly, but if I change the item quantity and update the cart, it defaults back to the product ID number.
What else do I need to change for the 'full details' to display the SKU (not the product ID) correctly once the cart is updated?