Need help copying demo to use with magic slide

[LHcause714]

I bought the orig devil may cry 3 demo from japan off of ebay. I cannot get the game to work with my magic slide. It goes through the intro vids but when i click start mission the screen goes black. I heard I might need to make a back up copy and use special load on magic slide. I know how to use magic slide but I have never made a copy of a game or demo, and have no idea how to do it. Could someone please give me instructions as to how I should go about this problem. Thanks, your help would be much appreciated.