Great contribution! I've almost got it working... However, if I have multiple "Ship to" addresses in my address book, and switch to one that is not the primary, the shipping cost goes away, and I am unable to proceed. I get stuck on the "checkout_shipping.php" page. I am only using FedEx ground, and no other shipping methods. I wanted to make sure that the zone import went okay, so I set up several addresses in my address book with different zip codes. None of them worked. At first I thought there was a problem with the zone imports, but after pulling my hair out for hours-- uninstalling/reinstalling, hand editing the SQL, etc, etc... I finally went in and simply changed the zip in my "primary" address. This worked (I was able to see different rates for different zip codes). I have a feeling it has to do with the checkout_shipping.php or maybe the checkout_shipping_address.php file. If I go into the address book and set one of the *other* addresses as my default, it still does not work-- the shipping module does not load. I even went in and deleted the contents of the entire sessions table in the database. Frustrating. Any ideas?