A plugin with this code on global_start hooks works, but, then no one can login because they are guests until they login...
PHP Code:
if (defined('IN_FRNR') && defined('FR_UTILS_INCLUDED') && !is_member_of($vbulletin->userinfo, 5, 6, 7))
{
fr_standard_error("You do not have permission to use this app.");
}
It only allows usergroups 5, 6, and 7 to use forumrunner... it's a start anyway.