OK, after much trial and error, it finally worked.
I'm a little confused though, and perhaps it's because I'm using a Mac, but what then would be the difference between simply linking to a .pdf file and "uploading" a .pdf file.
In the attachment feature, I was hoping users would be able to click on something and that something would load to their desktops. But after playing around with the attachment feature, I don't see a difference between linking to a URL and clicking on the "attachment."
Hope that makes sense.
