Hi,
We can't access to your website which is protected by user/password.
If you have a complete blank page, please activate the debug mode or change the "error reporting level" to "maximum" in your joomla global configuration.
You will find some explanations in our F.A.Q. too :
www.hikashop.com/support/faq.html
( Blank page )
It is also possible that your checkout workflow is uncompleted.
At this moment I will recommend you to post a screenshot of your checkout workflow 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.