Need help with my newest MP4 player?

I bought an MP4 player from China last week. Once I received the player, I was so happy with its beautiful looking. But I am sad with its terrible manual and its software when I turn on it. The device has marked on the player itself saying that it is an AVI player. It contains a demo avi file which plays reasonably well.

I tried to load up some avi files which play on my computer. But the portable player says incorrect format. I think the problem is that I can not understand functions of player fully. After I tried several times, I still can not upload .avi file.

Can some one suggest what we can try in this situation? Have you come across this situation before? And have you bought any MP4 player from china? I think I have been cheated or the player had problem before shipment. Anyone help me?