[Admin]

Err I'm in a bit of a hurry, but try replacing this in memberlist.php:

  $users=$DB_site->query("SELECT *
                          FROM user,userfield
                          WHERE $condition AND

with this:

  $users=$DB_site->query("SELECT *
                          FROM user,userfield
                          LEFT JOIN usergroup ON usergroup.usergroupid=user.usergroupid
                          WHERE $condition AND

then try using $user[title] in the memberlistbit template.

Hope this works.