Tracking Downloaded by registered email

This one is quite essential for me - being able to see in workflow who downloaded what from that particular gallery and with their registered email. I know I can scroll through users that registered, but this doesn’t do the job; I need to be able to select only the images downloaded by certain person/people who entered their email.

Usage scenario example:

Corporate headshots - 50 employees shot, only 40 downloaded their images with their registered email address; I need to have a list of who downloaded what so I can have a clear overview of who needs to be reminded to download their headshots.