I do not know why you would need to do that but to allow it to work, you need to use the code in RED:
Code:
if (!IS_ADMIN) {
        // insurace addition
        if (MODULE_SHIPPING_UPSXML_INSURE == 'False'){
            $this->pkgvalue = 100;
        }
        if (MODULE_SHIPPING_UPSXML_INSURE == 'True'){
//            $this->pkgvalue = ceil($order->info['subtotal']);
     $this->pkgvalue = $_SESSION['cart']->show_total();
}
        // end insurance addition
}
This prevents that code from running in the Admin as that is something that exists in the Catalog ...