redirect to blank if user not registered/logged in

-- HikaShop version -- : 1.6.0
-- Joomla version -- : 1.5.26
-- PHP version -- : 5.4.4-14+deb7u3
-- Browser(s) name and version -- : chrome/ie
-- Error-message(debug-mod must be tuned on) -- : None.. blank.,.

Hi

I have an old site and an old shop which has been running smoothly for years now..
it's running an old version of hika on J1.5.
I simply haven't had the time to update it.. which I should ..

I had an attack on the site which was fixed.. but now the landing page for customers who go to check out but doesn't have a registered user is redirected to first:
when clicking the checkout button in the Cart module it first goes to:

/index.php?option=com_hikashop&ctrl=product&task=updatecart&Itemid=294

a split second later it redirects to:

/index.php?option=com_hikashop&ctrl=checkout&Itemid=294
(which appear to be the registration page)
but then it redirects again to:

?option=com_hikashop&ctrl=checkout&task=state&tmpl=component&Itemid=294&field_type=address&field_namekey=address_state&namekey=country_Denmark_57

which is just blank..

Can you guys help..

I know it's an old site and old shop software.. but it worked before...

Here's hoping