Hi Terra, if it works on some but not others, have you got any free download restrictions in place, such as the Include or Exclude tick box on the general settings page, or the Advanced Product Restrictions settings page? Or if they're free because they're on 100% discount, have you got the option ticked to include discounted items?

I have it set to include products with a certain category. And all the products are correctly categorized.

Open a tech support ticket for me please so I can take a look at your site backend, give your settings a once over. Post the site admin details along with a link to a product that's working and a product that's not working.

https://wpenhanced.com/support/add-ticket/

It just seems like it's being very buggy. I some places it shows the download button, but instead of the pop up showing to log in to download it has the cart pop up and nothing being added. Some buttons say add to cart and to the same thing. And some buttons say download and then the button just turns black and nothing happens when clicked. And then some buttons work perfectly.