Domain mapping - top level admin link

Hi, I have recently purchased the latest domain mapping plugin in order to update my older version.

Bit of a noob question, but in my previous version the link was a top level link, whereas the new version is a submenu under the tools.

I looked and isolated the file I think I need in classes > Domainmap > Module > Pages.php

..line 164 $this->_admin_page = add_submenu_page( 'settings.php', $title, $title, 'manage_network_options', 'domainmapping_options', array( $this, 'render_network_options_page' ) );

I'm trying to change to add_menu_page with no success. Can you help?