How to Include PHP files in Vbulletin?

I want to include a php file into FORUMHOME so it displays on the main page,vBulletin version is 3.8.4 and plugins are enables. I have tried php includes but it doesn't work.

I have tried to create a Plug-in for global_start with these contents:

ob_start();
include('path/to/this/file/myfile.php');
$includedphp = ob_get_contents();
ob_end_clean();

But when I turn it on my forum displays a blank white page

Anybody know how to do this?

Thanks