Some Categories no full images, thumb images yes

[bestcons]

For clarification, my "products" are historical pictures such as postcards. So the product is an image, stored in images/stories/virtuemart/products.
I made a website to test full conversion to Virtuemart 2.0 and noticed that from some Categories all full images are missing in Details, where most other Categories have them. I use VM 2.0.8.
I created for test purposes a test configuration (Atest), including 2 images, one that has the full image (F024022) and one that shows the error message (F100203) for which I selected the zip icon. You can see the Category via www.dedecanije.nl/index.php/component/virtuemart/atest and click on Details.
Any suggestions?
Regards, bestcons

[bestcons]

After trial-and-error I found that if I change the image extensions from .JPG to .jpg, I can see my full images too!!!!! So nothing to do with Categories, the extension is case sensitive!! This would differ from VM 1.9.
Can someone confirm that this is indeed the case or is there a setting in configuration where I can select.
Anyhow, a lot of work to be done.
Regards,
bestcons