I haven't fully tested this and I'm no vbulletin expert but so far it works.
In the login box code find
PHP Code:
if ($vbulletin->userinfo['userid']!=0) {
change to
PHP Code:
global $vbulletin;
if ($vbulletin->userinfo['userid']!=0) {
It works the same for the other code snippets like no ads for members below.
PHP Code:
<?php
global $vbulletin;
if ($vbulletin->userinfo['userid'] <1) {
?>
your ad code here
<?php
}
?>
note: I have Wordpress/Vbulletin Bridge installed so global.php is already called. if you dont and this doesn't work for you try adding the requre once code to the top of the wordpress index.php