[Forum] Create ad - include PHP file

[n000b]

I'm trying to create an ad using vB4's new Advertising module, that includes a PHP file to get the actual ad HTML.

I read that you need to use a plugin to include a PHP file, so I created a plugin with this code (note: I've got $ad_html = 'testing'; rather than including a file just for testing purposes for now):

ob_start();
$ad_html = 'testing!';
$ad_html = ob_get_contents();
ob_end_clean();

I selected "global_start" as the hook location and made sure that the plugin was active.

I then created a new ad in the "Above Footer" location and for the HTML, entered:

{vb:raw ad_html}

I made sure it was active and saved it, but the ad is not showing on my forum. Any ideas why?

[n000b]

Anyone?