in the main .php files witch u are having problem with (such as details.php, member.php, lightbox.php and so on) at the end find:
//-----------------------------------------------------
//--- Print Out ---------------------------------------
//-----------------------------------------------------
add before:$categories = get_categories(0);
if (!$categories) {
$categories = $lang['no_categories'];
}
$site_template->register_vars("categories", $categories);
unset($categories);