Okay Michael has said avatars are only pulled from the database as such
http://walkonzone.com/vboard/avatar.php?userid=183
If your users are using hard linked avatars it does not work.
open your integration file vb3.php and find this line
$userprofile[6] = "<img src=\"{$Globals['vbulletin']}/image.php?u=$cuserid\" border=\"0\">"; // Avatar
change it to this
$userprofile[6] = ""; // Avatar