Routing - ignore first segment

Have you tried specifying all of them? There are no optional setting, you need to manually specify all routes segments.

PHP Code:

$routes->add( '(:segment)/(:segment)/(:segment)/(:any)', '$2::$3/$4' ); 
$routes->add( '(:segment)/(:segment)/(:segment)', '$2::$3' );
$routes->add( '(:segment)/(:segment)', '$2::index' );
$routes->add( '(:segment)', 'Default::index' );