Currently there's a confusingly-named 'Custom Checkout Dialog' option for the 'Order Ticket' button, which is basically a wrapper for designers/developers to put their own custom button in rather than using the super basic button offered by Eventive. For some reason this wrapper can only work with event IDs and not with pass bucket codes. Please either offer one for passes too or update the existing one to work with both passes (bucket codes) and tickets (even IDs).