Hi,
You have a PHP fatal error.
Please check your PHP error log in order to have the error message.
You can also set the "error reporting" to "maximum" in your Joomla global configuration ; and activate the "debug mode" in your Joomla global configuration.
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.