Na mój rozum to taki kod powinien działać
$this->default_routes['category_rule'] = array(
'controller' => 'category',
'rule' => '{parent_categories:/}{rewrite}/{page:/}{page}/', //edit rule
'keywords' => array(
'id' => array('regexp' => '[0-9]+'),
'rewrite' => array(
'regexp' => '[_a-zA-Z0-9-\pL]*',
'param' => 'category_rewrite'
),
'meta_keywords' => array('regexp' => '[_a-zA-Z0-9-\pL]*'),
'meta_title' => array('regexp' => '[_a-zA-Z0-9-\pL]*'),
'parent_categories' => array('regexp' => '[/_a-zA-Z0-9-\pL]*'),
'page' => array('regexp' => '[0-9]+', 'param' => 'page'),
),
);
a nie działa:(