Problem adding products to my new category

I have a number of category's but I have recently added a whole new product range called packaging products, Within this category there are a number of sub categories.
One of these appears like this
http://www.jbconline.co.uk/index.php?main_page=index&cPath=17
the products are listed but all I see is the background image repeating iteself.

I tried to create a new sub category and move the products over one by one. However as soon as one product was moved over the same problem occured.
Packaging Tape is the new sub category and Self adhesive tape is the old one.
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Any help would be appreciated

Something in these categories is causing an error. The page output stops abruptly after the featured sidebox, which is why you see the background repeating and not covered by the center column etc. What is different between these subcats and others?