What file holds the shipping logic for Downloads

Good evening everyone - I am experiencing an issue with my downloadable files.

Basically, the downloadable files are being treated as regular products (shipping and no download link) in my main template. I have verified that the file settings are all correct.

To further trouble shoot, I switched my store to the classic and another 3d party template and the downloads worked perfectly for both - skipping the shipping and offering the file link.

I am at a loss as to what to do to fix this problem but my first thought is to compare the files that hold the logic that excludes the shipping and so forth from downloadable products.

Does anyone know which file this would be? And otherwise, does anyone have any thoughts?

Thanks for any help in advance!

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