Multiple problems with zero balance orders

After some research on why these receipts were being printed, it looks like UberPOS was built to trigger the receipt whenever the balance of an order hits $0 or less. I don't know why this is, since it seems logical that instances would occur where a zero balance would need to be carrier and/or an order with a zero balance would need to be marked as completed (donations or freebies still need to be removed from inventory). I made two changes, one to uberpos.module and one to uberpos.commands.inc to get the desired behavior. Basically, I set the receipt to only be triggered by an order status of complete and instead of saying an order is already paid when you hit a payment method, I set the order status to completed and display a thank you message.

Here's the code I used in uberpos.module

  // if order status is completed UberPOS will display the print dialog.
  if ($order->order_status == 'pos_completed') {
    $times_printed = uberpos_receipt_times_printed($order->order_id);
    if ($times_printed == 0 || $_SESSION['uberpos_reprint'] == TRUE) {
      module_invoke_all('uberpos_paid', $order);
      $js['receipt'] = uberpos_get_receipt($order);
    }
  }

Here's the code I used in uberpos.commands.inc (around line 224)

    else {
	  //set order status as completed
	  uc_order_update_status($order->order_id, 'pos_completed');
	  $order = uc_order_load($order->order_id);
	  
	  // set clear message with order status
	  uberpos_clear_message(t('Thank you for shopping!'), array('clear_order' => TRUE));

    }
    return $type;