How to remove the default image shown in an indivdual product page?

Hi,

I am using MarketPress and I have used it such that i have used the featured image as well.

Is there a way where I can use the featured image such that the featured images are shown when the products are listed ( for exampe here : http://www.sagaegroup.com/store/products/ ) while the main image in a single product page ( for example : http://www.sagaegroup.com/store/products/sample-product-2/ ) is being disabled?

If the main image in a single product page cannot be disabled, may I know which part of the plugin do i have to edit?

Thanks!