Примерно ик?   
class ControllerShippingMyModule extends Controller {
    private $error = array();
    public function index() {
        $this->load->language('shipping/mymodule');
        $this->document->setTitle($this->language->get('heading_title'));
        $this->load->model('setting/setting');
      
#......... синдартный код обычной досивки
        $this->template = 'shipping/mymodule.tpl';
        $this->children = array(
            'common/header',
            'common/footer'
        );
        $this->response->setOutput($this->render());
    }
  
    public function getData() {
        $this->mymodule-getData();       
    }
    private function validate() {
        if (!$this->user->hasPermission('modify', 'shipping/mymodule')) {
            $this->error['warning'] = $this->language->get('error_permission');
        }
        if (!$this->error) {
            return true;
        } else {
            return false;
        }
    }
}