Weee! Now it works :D
By using this code:
{NAV_LIST_UL:F,2,4}
[PHP]
if(isset($GLOBALS['LEVEL_ID'][2])) {
$level_id = $GLOBALS['LEVEL_ID'][2];
echo '<div class="nlu_navi1">'.LF;
echo '{NAV_LIST_UL:F,'.$level_id.',,act_path,active}';
echo '</div>';
}
it now shows the menu the way I want it. It was ...