Update Order Total on Checkout Payment Page

[lilpenny1316]

I followed the instructions on this forum posting (http://www.oscommerce.com/forums/topic/356497-zero-total-checkout-after-coupon/) so that people could checkout with zero total after entering a 100% off coupon code.

 

I would like to add a refresh button to the Checkout Payment page so that after entering their coupon, the user can refresh the page and a new message appears to notify them that they do not have to select a payment and to hit Continue to complete the payment. Is there a way to update the order total on that page, so that message can appear? On checkout_payment.php the value of $order->info['total'] is the total before discount is applied, which I think is the issue.

 

Thanks!