I do think you should make it more clear on the Homepage that you are using a seperate free Software (MediaPortal) because if I didn't know that before visiting your site I would think you're selling your own software. But if the MP team is ok with it who am I to judge...
Who licensed that? ^^Remember this product is NOT a demo, it's a fully licensed copy of an amazing multimedia centre which allows you to manage all of your media needs from an easy to use control panel.