if you have a category column in the cart, you can use that to apply the discount to the category:
"based on items with a specific value"
Total of "Quantity" Where "Category" has a value of "Some category" "Times" "0.1"
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.