It's all in the vbulletin code so asking their support forums for help could prove more fruitful.
If nothing sets that $bbuserinfo then it will be false all the time. Do you have the code to read the user data from the database in the punkera.net/index.php file?
If you check if ($userid) I think it's always false (except the rare case of user id being 1). I think you should check if(isset($bbuserinfo['userid'])) instead. I don't think if(isset($userid)) works either because you actually set it there.
8 minutes here.
Too bad I didn't get here earlier.
Try EasyPHP: www.easyphp.org . It's basically n*next + finish installer for all the apps you need (Apache, PHP, MySQL) in Windows environment. Be sure to pick the right language in the installer as I picked French. The language is easy to change later though.
The website you create should be somewhere near C:\Program Files\EasyPHP1-7\home depending on your installation options and you can access it with your browser at http://localhost. The rest of the options are explained in the easyphp site and the accompanying files.