Require one or another product when purchasing specific item?

I have an item that if a customer wants to buy that item I want to require them to purchase one of x-number other additional items. It seems with CS-Cart’s Required Products addon that if I add the product to the cart, the cart automatically puts ALL items that are listed in the Required Products tab into the cart at checkout (plus the main item). I want them to be able to choose what other required product they want.

Any ideas?