public function renderTemplate($key, $additionalData = array())
    {
        if (!isset($this->templates[$key])) {
            return '';
        }
        
        $output = '';
        
        // Render the template files
        foreach ($this->templates[$key] as $priority => $templateFile) {
            $output .= $this->searchRendererAndRenderTemplate($templateFile, $additionalData);
        }
        
        return $output;
    }