Due to how this site is stored in the Amazon S3 cloud, the normal avatar function of the BuddyPress system doesn’t work.
If you want to change your avatar/profile picture, you must do it at the Gravatar website. It’s not hard.
Also, if you want to change your header image on your person page, you have to use an iPhone or iPad. For the life of me, I can’t explain it, but it doesn’t work on computer.
For more detailed information about this, please go to this article, Debugging Pixels.