I'm trying to set up the following promotion: for every 5 bumgenius diapers purchased, get the 6th one free (unlimited quantities: buy 10, get 2, buy 15, get 3 and so on). Because the free item has options, it cannot be used as the "fixed price product" in the promotion. Therefore, I'm attempting to set it up as a percentage off. I think I just about have it figured out. I have it set up to give a 16.9% discount when the 6 diapers are purchased with the discount only applicable to the specific diaper. The problem I have now is it continues to give the discount beyond the 6th diaper. I need the promotion to apply to 6, 12, 18 and 24 diapers only. Any suggestions/ideas? TIA!