Nope. You should now power down, and flash it with developer.

At this point, re-read Roger's instructions, and follow them: the builder does partly prepare the disk, but not the music partition (at least not properly). If you just leave it the way it is at the moment, the player will appear to start up OK, but will give you all sorts of problems with playlists (doesn't see them, etc). You still haven't said how big your disk is.