Quote Originally Posted by lolwaut View Post
You're right. I misunderstood.

Actually, now that I am fully testing this, if the gift card field is populated with anything but $0.00 and the order is submitted WITHOUT clicking the "Apply" button, Zencart actually throws an error: Your order's details have changed. Please review the current values and re-submit.

@carlwhat For this to be implemented properly, the checkout submit process would need to ignore that field. This might be more complicated than I initially thought. Does your plugin address this?
It's actually One-Page Checkout's processing that issues that message. That's because the order (upon submittal) contains that GC value, but the previous record of the order didn't. That's to 'protect' the customer (and the store) from any misleading charges.