More backgrounds can be found here: http://imgur.com/a/P9BFr
More renders (characters) can be found here, without watermarks: http://imgur.com/a/ydViG
You can paste the URLs from the albums in "Provide your own" on this theme's page,
or download the images and use them for "Upload your own".

Official topic: http://myanimelist.net/forum/?topicid=1387149

My Easy Stylish themes (the easy background and easy character themes may override the MMO one)
Easy Banner: http://freestyler.ws/style/119620/myanimelist-customize-your-banner-easily
Easy Background: http://freestyler.ws/style/119619/myanimelist-add-custom-background-images-or-color
Easy Characters on the sides: http://freestyler.ws/style/128636/myanimelist-add-custom-characters-on-the-sides

Remove the new footer: http://freestyler.ws/style/119570/myanimelist-remove-blue-footer-social-media
Remove the new links: http://freestyler.ws/style/119617/myanimelist-remove-new-links
Restore the profile button: http://freestyler.ws/style/119572/myanimelist-restore-profile-button
Recolor the message bubble: http://freestyler.ws/style/119660/myanimelist-re-color-the-bubble

All Stylish themes for MAL to customize MAL easily:
http://myanimelist.net/forum/?topicid=453219&show=0#msg39817666