3rd party site including vbulletin framework can't display templates

[Disasterpiece]

Hey

I'm trying to create my own page with vbulletin vars being available according to this guide:
https://vborg.vbsupport.ru/showthread.php?t=228112

I'm using a cms on the domain root http://example.tld/ and the forum being at http://example.tld/forum

I created a "bridge class" which gets included to initialize the vB bridge:

PHP Code:

class vBBridge
{
        static private $vb_name = 'xxx';
        static private $vb_user = 'xxx';
        static private $vb_pass = 'xxx';
        static private $vb_table = 'vb3_session';
        static private $vb_usertable = 'vb3_user';
        static private $vb_cookie = 'bb_sessionhash';

        static private $vb_db = null;

        static private $vb_sessioninfo = null;
        static private $vb_userinfo = null;

        static public $precache_tpl = array();
        static public $precache_phrase = array();
        static public $precache_datastore = array();
        static public $precache_tpl_special = array();

        static public function init_vB() {
            define('THIS_SCRIPT', 'portal');
            define('CSRF_PROTECTION', true);

            // ################### PRE-CACHE TEMPLATES AND DATA ######################
            // get special phrase groups
            $phrasegroups = self::$precache_phrase;

            // get special data templates from the datastore
            $specialtemplates = self::$precache_datastore;

            // pre-cache templates used by all actions
            $globaltemplates = self::$precache_tpl;

            // pre-cache templates used by specific actions
            $actiontemplates = self::$precache_tpl_special;

            // change this depending on your filename
            chdir ('./forum');
            require_once('./global.php');
            chdir ('../');
        }
} 


So far so good.

the init_vB() function gets called somewhere down the road, inside the cms like this:

PHP Code:

include_once('./lib/vbbridge.class.php');

vBBridge::$precache_tpl = array('cms_toplinks');
vBBridge::init_vB(); 


after this call, I can use the $vbulletin var everywhere, so this works.

BUT:

now I'm trying to get a simple vbulletin template, "cms_toplinks".
To accomplish this, my test code looks like this:

PHP Code:

global $vbulletin;

$templater = vB_Template::create('cms_toplinks');
$templater->register_page_templates();
$str = $templater->render();

var_dump($str); 


[using print_output($templater->render()) as suggested in the guide gives me an error]

The output in the CMS is this:

string(74) "<!-- BEGIN TEMPLATE: cms_toplinks -->

<!-- END TEMPLATE: cms_toplinks -->"

So the vb framework is loaded, but it doesn't find my template. Why?

I created the template with the same name (yes, case-sensitive) as a child template to the MASTER-STYLE as suggested in the guide, but still. Doesn't find the template.

Any ideas?