NDS games help.

Hi all,
I would like some help.
I just bought a Personal Media Player for the Nitendo DS/DS lite.
The thing is I can't make it play any of the games I've downloaded.
It has a drag and drop system, when I put in the cartridge in the DS and open the file, it's empty. :(
It won't recognize any of the nds games....On the box it clearly says it can play games, videos and music. I'm disappointed.
Here is what the product looks like: http://www.nextag.com/DATEL-Personal...35/prices-html

If anyone can guide me so I can actually play some games on the blasted thing it would be greatly appreciated.

Thank you for your time.
ShadowsServant.

I returned the damn thing, turns out it could only play copyrighted material. Go figure.
That was a total bust.