BuddyPress.org

maybe interim solution – autoassign a group admin at group creation (sample code, just need to have a account setup and replace the user_id. ie, in my case i use a dummy groupadmin user for all groups)
http://etivite.com/groups/buddypress/forum/topic/quick-tip-auto-assign-member-as-group-mod-or-admin-to-new-groups/#topic

though, i don’t know if that fixes the original issue with a legacy creator_id (then again, i don’t see any big references to that col – besides logging)