New pics show as options to choose, but after selecting and confirming choice, page reloads and avatar does not change in profile.
Ensure the filenames for the new images have no spaces, no special characters, basically simply alphanumeric names. If not then please rename them and try again. Also ensure if you're using any form of Joomla caching that it has been purged after your change as your previous profile image may have been cached.
BTW, after 1000 years maybe CB could update their crappy old avatar pics. Oddly, it's been years and CB looks the same, much outdated.
The gallery images are simply placeholders. You're supposed to replace them to fit your needs. They'll likely be replaced with CB 2.0.