if ($mg_id) {
include_once("$g4[path]/head.php");
if ($mm_id)
include_once("$mw_mmenu_skin_path/mmenu.main.skin.php");
else
include_once("$mw_group_skin_home_path/group.home.skin.php");
include_once("$g4[path]/tail.php");
} else {
include_once("$g4[path]/head.sub.php");
include_once("$mw_index_skin_head_path/index.head.skin.php");
include_once("$mw_index_skin_main_path/index.main.skin.php");
include_once("$mw_index_skin_tail_path/index.tail.skin.php");
include_once("$g4[path]/tail.sub.php");
}

스킨인데요..
$mg_id, $mm_id 가 무엇인가요?