Hi,
In HikaShop 2.2.2, we change the email system in order to have a HTML email template in one file and the PHP code in another file.
The interface does not propose you to edit the php file yet but you can access it directly in the folder "media/com_hikashop/mail/".
The PHP file is the file called "preload", you can copy the "preload" file into "preload.modified" in order to create an override (so you will keep your modification with updates).
It is planned to improve the email edition so the preload will be accessible in the backend too.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.