Hello :)
I love this contribution, and have it working wonderfully on several sites.
However, one client has the Quantity Price Break installed as well, for retail customers. They want to have retail customers buy using the quantity price breaks, but allow Wholesale customers use the discount coupon and receive a percentage off the FULL retail price (before the quantity price breaks)
Is there a way to alter the code to have this module go to the database and pull out the retail price, and calculate the quantity and price?