Hey, make sure you set your group admin permissions to "Subject to Vote" or "Are Not Allowed". There has been two notorious group hijackers for over a month now who apply as a co-founders, delete all the artwork in the gallery and favorites, and replace it with gore, scat and porn.
As an example:
www.deviantart.com/link-club(the disgusting stuff has since been removed, but the galleries have been completely wiped out)