File Download Log

Everytime a file is downloaded there's an entry made in the File Download Log.  

To access it go to Downloads → Reports → Logs and choose File Downloads from the dropdown.  Once there you'll see a screen similar to this:

The Downloads column lets you click a download and see only the rows for that item.

The User column lets you click a user and see only rows from that user.

The Payment ID column lets you click and ID and see information about the original transaction.