well, that would be a bit odd… assigning actual users to the guest usergroup would really just affect permissions… they would still be members… probably better to create a different usergroup and give them the permissions you want so the other member/guest checks would work as expected…
still, assuming everyone you wanted to count was in a usergroup, you could probably use this to adjust the counts:
add_filter('sph_stats_members_count_query', 'my_stats_query');
function my_stats_query($spdb) {
$spdb->join = array(SFMEMBERSHIPS.' ON '.SFMEMBERSHIPS.'.user_id = '.SFMEMBERS.'.user_id');
$spdb->fields = 'COUNT(DISTINCT '.SFMEMBERS.'.user_id) AS count';
$spdb->where = SFMEMBERSHIPS.'.usergroup_id != 1';
return $spdb;
}
the usergoup_id != 1 would just need to be updated with the sp usergroup you wanted to exclude…
think it will work, but have not tested and could give odd results depending on how users and memberships were handled… but give it a try…