Hi Discovery, I'm afraid the instructions you've followed so far are no longer much use, since the BBC changed the format of the streams in February.
Take a look at the solution proposed by pushedtempo in this thread, see above: http://www.runeaudio.com/forum/bbc-radio-t546-20.html#p5633. The only possible snag is, that according to the minim website (http://minimstreamer.com/index.html) it is "free to download and use until 31 December 2015" - we don't know what happens after that.
This has been a very stable solution for me.