A proof sheet is a lower resolution document of a collection of assets. If you have 50 photos (100MB ea), you make a "proof sheet" that shows a recognizable thumbnail of each photo all together in a doc (often a pdf) that may only be 2 or 3 MB in size. WF DAM already makes thumbnails in the detailed view of the Download Tracker, so selecting the assets and then exporting to a pdf would be great. Ideally, once the group of assets is identified there would be a "notification" button that would also launch an email to the email addresses associated with each asset (who downloaded), and a pdf attached to the email along with standard message text.