WP Super Large Menu Problem

From first view this seems to be tough job, but actually even I having small skills of php could solve this problem just adding following code to my custom walker class:

if ( $depth == 1 ) { // remove this statement if depth check is not required
  if (wp_get_nav_menu_object($item->title)) {// checking if item name matches to menu name
     $item_output .= wp_nav_menu( array('menu' => $item->title, 'container_class' => 'mgmenu_tabs_panels', 'menu_class' => '', 'menu_id' => 'section'. $item->ID, 'echo' => 0 ));
   }
 }

as simple as that.
This script will check if any created menu name matches sub menu item name, and when they match script will add all items from that matching menu.

Basically this script allow you divide any large menu into many smaller ones.