What a great invention. I am playing backups and homebrew games without any errors or freezes at all with my new DS Lite.
Copying and pasting it all that is required. You first copy the firmware onto the miniSD card and then transfer your games onto the card as well. Plug it into the M3 DS Simply and plug it into the slot 1 of the DS Lite. It cannot be made any easier.
The kit came with:
-M3 DS Simply
-mini CD with firmware and a few other tools on it as well