template switch addon

[hugo13]

What is the init_templates when I paste it in the override folder the site goes blank.

the only difference to the original file, are the lines 38..50

/**
 * The actual template directory to use
 */           
 $template_dir = 'classic'; 
   if(isset($_GET['template_switch_id'])){
    zen_setcookie("zctemplate", $_GET['template_switch_id'], time()+(60*60*24*365));
    $template_dir = $_GET['template_switch_id'];
  } else {
      if(isset($_COOKIE["zctemplate"])){
        $template_dir = $_COOKIE["zctemplate"];
        zen_setcookie("zctemplate", $_COOKIE["zctemplate"], time()+(60*60*24*365)); 
      }
  } 

remove the closing

?>

at file-end; maybe there are chars after