No popup window after adding article to basket

-- url of the page with the problem -- : www.yohocards.nl
-- HikaShop version -- : 2.2.3.
-- Joomla version -- : 3.2.1
-- PHP version -- : 5.3.10
-- Browser(s) name and version -- : firefox 26.0
-- Error-message(debug-mod must be tuned on) -- : Error_message

In the general settings for the shoppingbasket there are 3 options for the action after adding an article to the shoppingbasket:
- stay on the page and show a popup message
- proceed always to the shoppingbasket
- stay on the current page

I have choosen for the first option but the popup window does not show, instead I get a blank page, the same counts for the other two options? If I click on the menu to go to the shoppingbasket, nothing happens on the first click, page stays blanc, after the second click the shoppingbasket page appears.....
I have been going through all the settings over and over again, what do I overlook?

Hi,
We will continue through this thread .