Hi Alan,

I would check that you have working versions of

admin/includes/modules/update_product.php

and the likes of

admin/includes/modules/product/collect_info.php
admin/includes/modules/product/preview_info.php

uploaded.. if you have done something wrong in merging/adding those files then the uploaded image may not be getting saved correctly (it is handled by the three files above, as is the URI mapping).

Hope that helps!

All the best...

Conor
ceon