Hi,
In the order listing, when you confirm an order in the HikaShop backend, you can also modify the email content. Because the order is not yet confirmed, the mail content does not include the HikaSerial content.
Before HikaShop 2.2.1, the same problem was in the order page itself.
That's why we made some modifications in HikaShop 2.2.1 (and 2.2.2) in order to improve the way that emails are send.
So now we you confirm in the order page, you can simply check that you want notify the customer and the default email will be send (and you can modify the content).
Otherwise you can send manually an email (and with HikaShop 2.2.2, we put a nice template with a lot of data, like the order status notification email).
I recommend you to not confirm the order in the order listing (if you want to send an email in the same time).
This part will be improve in the future.
Regards,