As it turned out I managed to get the bike MOT'd here without the need to change the speedo. It seems the information I got was wrong and as a MPH speedo is what the bike was manufactured with it is ok.
I tried downloading the mpg again but no joy, it gets to about 100 k then stops. When i view the file it opens but is obviously not big enough to see anything, looks like I'll never see what all the fuss was about. Unless your able to send it to email@example.com