virtuemart how to show category images

Apperently this is common problem, which doesn't help when looking around the internet for a soution. Heres some of the google search phrases I'd made.

virtuemart showing category thumnail

virtuemart show category images

This page http://www.gjcwebdesign.com/no-thumbnail-images-in-virtuemart-category-view.html says that normally its a chmod problem but it wasn't in my case.

After searching countless posts I found where the code generating the category display would be. its on

themes/default/templates/common/categoryChildlist.tpl.php

and the code showing the category image is

ps_product::image_tag( $category["category_thumb_image"]

that was present so I wrote Hello World

And it worked - this means that the code is present that I need to display.

So why no thumbnail !!

This is when the pin dropped. Well in Virtuemart you have a category main image and thumbnail and although I'd added a category full image I hadn't added a thumbnail - Doh!!!!