Colin Hart

Thank you for that, works nicely and much more elegant than my solution, does it all in one place from the Control Panel and I can use this button only on the products I want it on. It was the [addtocart_url] piece I was missing before when I tried to add a custom button

Found a way to achieve what I want, I am using a child theme to keep my theme customisations in, I added the lines below to the style.css in the child theme:

h3.wpdmpp-product-price {
visibility: hidden;
}

Now just got to change the button text which I think can be done using the downloadmanager pro button image plugin and a custom image.