When using this plugin it updates the avatar/gravatar profile picture as well. However, say you backup your site and reinstall it / transfer hosts /etc. all of the avatar/gravatar images get changed back to the “Mystery Man” despite the custom images already added to the “Custom User Profile Photo”…

Going in and updating the user’s profile isn’t enough. The only thing that seemed to work was:
1) go into each profile remove the “Custom User Profile Photo”
2) Update the profile.
3) After update re-add their custom profile picture.
4) Update the profile.

After doing this it updates the gravatar/avatar photo. Unfortunately when you have 100+ users this is a huge hassle. Haven’t looked into the code yet, but this seems like something that should be a fairly easy fix.