I'm having a problem wherein my product does not show up in the shopping cart as a downloadable product in some cases. When it's a Free Download with no other attributes it will.

When I create other products with four other 4 attributes (Body Style, Hair Style, Comments, Web Hosting Option) the Download File attribute is not listed. It used to work and the shipping module would be skipped. Now, when implementing these multiple attributes on all of the products I sell, the shipping module shows up every time when they attempt to checkout and it wants to charge the customer. This has to be confusing for a customer to have to be asked what address to ship a download to. Does anybody know why it's not kicking in correctly? I've carefully followed the correct procedure for adding a downloadable product to the store. I've studied this implementation procedure far more carefully than any other aspect of Zen Cart. I've studied posts, the purchased user manual (page 211), web posts, and even Youtube tutorials. I just don't see why it's not working or what I may have done incorrectly. This is a lower order showstopper but the workarounds for an unsolved problem aren't pretty or easy.