If your connection at the test socket is sucessfull, and you suffer no further drop outs, a good plan would be to fit a ADSL XTE-2005 filter faceplate, also from ADSL Nation as well as the new master socket.
These have the advantage of preventing any problems which your extension wiring may cause to your broadband signal and provide the same connection as you get at the test socket. They come with full instructions as to how to fit them.