Fatal error: Call to a member function get() on a non-object

<?php
// Version
define('VERSION', '1.5.1.3');

// Config
require_once('config.php');

// Install
if (!defined('DIR_APPLICATION')) {
header('Location: install/index.php');
exit;
}

// Startup
require_once(DIR_SYSTEM . 'startup.php');

// Application Classes
require_once(DIR_SYSTEM . 'library/customer.php');
require_once(DIR_SYSTEM . 'library/affiliate.php');
require_once(DIR_SYSTEM . 'library/currency.php');
require_once(DIR_SYSTEM . 'library/tax.php');
require_once(DIR_SYSTEM . 'library/weight.php');
require_once(DIR_SYSTEM . 'library/length.php');
require_once(DIR_SYSTEM . 'library/cart.php');

// Registry
$registry = new Registry();

// Loader
$loader = new Loader($registry);
$registry->set('load', $loader);

// Config
$config = new Config();
$registry->set('config', $config);

// Database
$db = new DB(DB_DRIVER, DB_HOSTNAME, DB_USERNAME, DB_PASSWORD, DB_DATABASE);
$registry->set('db', $db);

// Store
if (isset($_SERVER['HTTPS']) && (($_SERVER['HTTPS'] == 'on') || ($_SERVER['HTTPS'] == '1'))) {
$store_query = $db->query("SELECT * FROM " . DB_PREFIX . "store WHERE REPLACE(`ssl`, 'www.', '') = '" . $db->escape('https://' . str_replace('www.', '', $_SERVER['HTTP_HOST']) . rtrim(dirname($_SERVER['PHP_SELF']), '/.\\') . '/') . "'");
} else {
$store_query = $db->query("SELECT * FROM " . DB_PREFIX . "store WHERE REPLACE(`url`, 'www.', '') = '" . $db->escape('http://' . str_replace('www.', '', $_SERVER['HTTP_HOST']) . rtrim(dirname($_SERVER['PHP_SELF']), '/.\\') . '/') . "'");
}

if ($store_query->num_rows) {
$config->set('config_store_id', $store_query->row['store_id']);
} else {
$config->set('config_store_id', 0);
}

// Settings
$query = $db->query("SELECT * FROM " . DB_PREFIX . "setting WHERE store_id = '0' OR store_id = '" . (int)$config->get('config_store_id') . "' ORDER BY store_id ASC");

foreach ($query->rows as $setting) {
if (!$setting['serialized']) {
$config->set($setting['key'], $setting['value']);
} else {
$config->set($setting['key'], unserialize($setting['value']));
}
}

if (!$store_query->num_rows) {
$config->set('config_url', HTTP_SERVER);
$config->set('config_ssl', HTTPS_SERVER);
}

// Url
$url = new Url($config->get('config_url'), $config->get('config_use_ssl') ? $config->get('config_ssl') : $config->get('config_url'));
$registry->set('url', $url);

// Log
$log = new Log($config->get('config_error_filename'));
$registry->set('log', $log);

function error_handler($errno, $errstr, $errfile, $errline) {
global $log, $config;

switch ($errno) {
case E_NOTICE:
case E_USER_NOTICE:
$error = 'Notice';
break;
case E_WARNING:
case E_USER_WARNING:
$error = 'Warning';
break;
case E_ERROR:
case E_USER_ERROR:
$error = 'Fatal Error';
break;
default:
$error = 'Unknown';
break;
}

if ($config->get('config_error_display')) {
echo '<b>' . $error . '</b>: ' . $errstr . ' in <b>' . $errfile . '</b> on line <b>' . $errline . '</b>';
}

if ($config->get('config_error_log')) {
$log->write('PHP ' . $error . ': ' . $errstr . ' in ' . $errfile . ' on line ' . $errline);
}

return true;
}

// Error Handler
set_error_handler('error_handler');

// Request
$request = new Request();
$registry->set('request', $request);

// Response
$response = new Response();
$response->addHeader('Content-Type: text/html; charset=utf-8');
$response->setCompression($config->get('config_compression'));
$registry->set('response', $response);

// Cache
$cache = new Cache();
$registry->set('cache', $cache);

// Session
$session = new Session();
$registry->set('session', $session);

// Language Detection
$languages = array();

$query = $db->query("SELECT * FROM " . DB_PREFIX . "language");

foreach ($query->rows as $result) {
$languages[$result['code']] = $result;
}

$detect = '';

if (isset($request->server['HTTP_ACCEPT_LANGUAGE']) && ($request->server['HTTP_ACCEPT_LANGUAGE'])) {
$browser_languages = explode(',', $request->server['HTTP_ACCEPT_LANGUAGE']);

foreach ($browser_languages as $browser_language) {
foreach ($languages as $key => $value) {
if ($value['status']) {
$locale = explode(',', $value['locale']);

if (in_array($browser_language, $locale)) {
$detect = $key;
}
}
}
}
}

if (isset($request->get['language']) && array_key_exists($request->get['language'], $languages) && $languages[$request->get['language']]['status']) {
$code = $request->get['language'];
} elseif (isset($session->data['language']) && array_key_exists($session->data['language'], $languages)) {
$code = $session->data['language'];
} elseif (isset($request->cookie['language']) && array_key_exists($request->cookie['language'], $languages)) {
$code = $request->cookie['language'];
} elseif ($detect) {
$code = $detect;
} else {
$code = $config->get('config_language');
}

if (!isset($session->data['language']) || $session->data['language'] != $code) {
$session->data['language'] = $code;
}

if (!isset($request->cookie['language']) || $request->cookie['language'] != $code) {
setcookie('language', $code, time() + 60 * 60 * 24 * 30, '/', $request->server['HTTP_HOST']);
}

$config->set('config_language_id', $languages[$code]['language_id']);
$config->set('config_language', $languages[$code]['code']);

// Language
$language = new Language($languages[$code]['directory']);
$language->load($languages[$code]['filename']);
$registry->set('language', $language);

// Document
$document = new Document();
$registry->set('document', $document);

// Customer
$registry->set('customer', new Customer($registry));

// Affiliate
$affiliate = new Affiliate($registry);
$registry->set('affiliate', $affiliate);

if (isset($request->get['tracking']) && !isset($request->cookie['tracking'])) {
setcookie('tracking', $request->get['tracking'], time() + 3600 * 24 * 1000, '/');
}

// Currency
$registry->set('currency', new Currency($registry));

// Tax
$tax = new Tax($registry);
$registry->set('tax', $tax);

// Weight
$registry->set('weight', new Weight($registry));

// Length
$registry->set('length', new Length($registry));

// Cart
$registry->set('cart', new Cart($registry));

// Front Controller
$controller = new Front($registry);

// Maintenance Mode
$controller->addPreAction(new Action('common/maintenance'));

// SEO URL's
$controller->addPreAction(new Action('common/seo_url'));

// Router
if (isset($request->get['route'])) {
$action = new Action($request->get['route']);
} else {
$action = new Action('common/home');
}

// Dispatch
$controller->dispatch($action, new Action('error/not_found'));

// Output
$response->output();
?>