Category Targeted Coupon Code - Issue with Multiple Categories

So, I have created a coupon code to target specific categories within virtuemart. I have selected specific for the coupon type. Everything works great if the customer only adds a product from one of the qualified categories to their cart and applies the coupon code. However, if their cart has multiple products, some from coupon targeted categories and some from other categories, the coupon code does not work. I get the message "Some of Your Products are Not Available for Discount with this Coupon". How can I set up a coupon code to target specific categories and not others and work no matter what the customer has in their cart? Targeted at the sku level would mean adding thousands of skus to include. That would be such a waste of time.

Hopefully there is an easy answer

Thanks

The category coupons should work as long as there are qualifying items in the cart, whether there are non qualifying items or not. I just tested this on v 1.3.2 and it works. I created a very simple coupon:
percent or amount: percent
discount type: specific
value:25
left everything else blank and selected 1 category. Then added a product from multiple categories and applied the coupon. It discounted the only product from the qualifying category.

You should be able to look at the configuration page and see what error "Some of Your Products are Not Available for Discount with this Coupon" corresponds to. If all your error messages are the same, make them unique, to pin down the true error.