sap brazil substituição tributária calculation issue

Hi All,

I am very new to SAP Brazil pricing and taxaction, recently i encountered an issue with substituição tributária calculation.

As per the user who raised the issue, the BX41 condition type on sales order was said to be calculation incorrectly by using invoice value instead of minimum price.

When i checked the configuration (transaction code J1BTAX) the calculation method was selected as "Base sub.Trib = invoice value or minimum price" and the minimum price and number of units fields were maintained in the special subscreen.

Question 1: When the calculation method = "Base sub.Trib = invoice value or minimum price", what exactly is the system preference of calculation the base sub. trib value?

Question 2: I also observed that the standard condition routine 320 has been assigned to all tax condition types in brazil pricing procedure. Need help in understanding the pricing routine. Can this routine decides the preference of invoice value over minimum price.

Thanks,

Arun.S