I have not got to the bottom of all the problems but there are at least 3
1) when a customer purchses an item from the shop - instead of being taken to the download they are being taken to a screen saying the purchase has not yet cleared. When you refresh the screen it goes to the result but the customer is told to wait for an email.
2) the Wpsc-single_product.php file is showing as inactive. As this is a file I have previously edited to include the item header on the individual produce screen it is again presenting a problem.
3) positioning of images has changes when you go into each product