OK back on track.... the order of your code looks OK at initial glance.
Have you tried putting in a redirect after your update behaviour takes place.
So using open-orders.php as an example change line 17 to
$WA_redirectURL = "open-orders.php";
Also, you might want to consider pagination so that it only displays 20 or so records on a page. That will speed things up immensely.
Cheers
Ian