Adding Products Directly to Shopping Cart

I finally got the plugin working once I discovered the conflict was with 404 Redirect.

Now when I attempt to buy a product by clicking Buy Now does not add the item immediately to the cart.

Instead it goes to the Shopping Cart page
/shopping-cart where there is a "Browse Products" link. I then have to select a product and click the Buy Now button again!

I am using the shortcode [mp_product product_id="2" image="0"]

I need the Buy Now button presented by the
[mp_product product_id="2" image="0"] shortcode to add the product to the Shopping Cart immediately, not having to select it again on the Products page.