The ability to translate Radio to N.Radio only works when the BS5 is the audio master (and I think without a BeoVision, you must connect the speakers to the BS5 for it to be audio master).
You can slave the BS3000 to the BS5, but then you cannot listen to BS3000 sources in your link rooms (at least this is how it worked when I tried to "slave" my BS9000 to the BS5 as master... well, now that I think about it, the BS9000 didn't behave well when slaved (non-responsive, sometimes messed up ML completely)... I guess it was my dealer who told me that the BS5 as audio master will not distribute a slave CD, Radio or AUX signal - take this for what it is worth - my dealer is correct about 50% of the time when it comes to BS5).
I also think when you turn on the Radio -> N.Radio translation, this also turns on CD -> N.Music translation. Although, you may be able to option program so that the BS3000 responds to Link-CD (as well as Link-Radio).
Stan