How can I create a coupon that applies to all products except for two particular brands that are spread amongst different categories?
Response:
Create a new top-level category for the excluded products, and add that category as an Additional Category to the products you wish to exclude from coupon application. If you do not want this category displayed to your customers, you can designate its visibility to "Internal" or "None." When setting up the Coupon, you may then select "Products in all top level categories except (new category)" as the Coupon Application.