Quote Originally Posted by lat9 View Post
OK, here's what corrected the issue for me. I made these changes to the eo_get_order_by_order_id function of /YOUR_ADMIN/includes/functions/extra_functions/edit_orders_functions.php:
Please do not apply the above code changes. Coupon processing (and adding cc_id to the session) currently takes place when the update button is pressed.

The "add product" button does not currently process all order total lines (ot_coupon is one of these). As a temporary workaround, after adding a product one should click the "update" button to update the order totals.