Ok, it's up to me to set up the symbolic link for doing redirected downloads. However, the documentation is pretty spotty as to exactly what to use.

My pub folder is:

/home2/webcastl/public_html/store/pub

My download folder is:

/home2/webcastl/public_html/store/download

The permissions are set on folders and files.

The notation for setting up a symlink is:
ln -s target_filename symlink_filename

But I'm not sure if Zen Cart needs the fully qualified directory map, or just the end folder as the symlink name.

So I'm thinking:

ln -s /home2/webcastl/public_html/store/download /home2/webcastl/public_html/store/pub

Or is it

ln -s /home2/webcastl/public_html/store/download /pub

Or is it

ln -s /home2/webcastl/public_html/store/download pub

Forgive me if I missed it, since I looked in the forum but couldn't find any specifics.