Okay, I'm back ... 17 hours, 5 tax rules, and well over 500 ZIP Code conditions later! I decided to input all of the conditions by hand since I'm a week away from launch and I can't find a programmer in that amount of time.

Anyhow, I've uncovered a very bizarre bug that only presents itself upon the initial completion of the checkout form (which for most people is the only completion of the checkout form). This bug impacts the proper calculation of Florida taxes against the shipping plus tax_subtotal.

Here's how the story goes ...

1. I have a shippable product.

2. I have a tax rule in Ubercart for 6% Florida Sales Tax specified to belorida applied to shipping and tax_subtotal. The related Workflow-NG rule is weighted a 5 (my shipping rules are weighted a 0) and correctly specifies Florida as the zone.

3. I have a tax rule in Ubercart for 1% Discretionary Sales Tax specified to be applied to shipping and tax_subtotal. The related Workflow-NG rule is weighted a 5 (my shipping rules are weighted a 0) and correctly specifies multiple ZIP Codes as OR conditions.

4. I purchase products (any products and any quantity) and select to "Checkout" from either the cart page or cart block.

5. I insert my Zone as Florida and my ZIP Code as any qualifying Florida ZIP Code (i.e., 32011 or 32038, etc.).

6. The shipping, taxes, and totals auto-calculate. However, the taxes are INCORRECTLY applied against the tax_subtotal only and not the shipping. A subtotal fails to appear at all.

7. Within the same checkout form, make a change to the ZIP Code (even if it's for a ZIP Code within the same tax rule) and step off the cell. You will find that the checkout form recalculates the taxes and totals, correctly displays a subtotal, and correctly applies the taxes to tax_subtotal and the shipping.

PLEASE, PLEASE give me a solution to this that doesn't require me to alter or recreate my tax rules. I've found that Ubercart and Workflow-NG don't really have any update/delete interaction once a tax rule is created. So, I don't want to have to make a change that requires me to scrap to 500 plus conditions that I created manually over a 17 hour period.

My associate suggests that at a glance it looks like it is because shipping (although weighted lighter than taxes) are not being calculated until the "Calculate Shipping..." button is pressed. So, the first time through the checkout, the shipping costs are not being considered prior to the taxes having been calculated once the user steps off the Zone and ZIP Code fields.