Hi,
There is a little checkbox "notify customer" which appear when the order status is changed.
It allows the administrator to send an email to the customer, to notify him.
We are currently finishing the new order interface for HikaMarket which new includes a "e-mail" button (like in HikaShop backend) to send an "order status changed" email.
The new interface contains "order history" too (and some interfaces for the multi-shipping).
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.