Custom single product page


Has anyone been able to create a custom single product page that works?

Using a mp_product.php file in the theme directory it works if a call to <?php mp_product(); ?> is made. But when trying to display it using the following <?php mp_product_price(); ?><?php mp_buy_button(true, 'single'); ?><?php the_content(); ?> it displays on the page but the ajax add to cart doesn't work and it takes us directly to the cart. The cart then shows "There are no items in your cart - go add some !"

Surely there must be a way to customise the layout of the single product page.