This is definitely the problem, as I disabled localisation and it works. Therefore advice would be to rewrite the code for international sites as it doesn't appear to function as it is.
However I'm now having other problems in seeing the multiple images attached using thickbox, despite the code being as specified above.
My desire would be that the first product image is displayed in the node (just that one) but then when you open up the thickbox, the other images are there using the next button. Does anyone have code to implement that? Sorry... I'm a bit new at this stuff so maybe this has been mentioned above but I followed the posts above and can't get it to work!