Try installing Beoplayer on your editing PC, then syncronise with the BM5. This should bring up the channels.
I think you can only use N.Radio with the BM5 only solution - unless there is something on the service menu. I dont have this setup so cant see for myself but I think it goes something like:-
In PC mode, (Beo4, list, PC).
Menu, 9, (brings up list)
0,0,Go (makes list go into service menu mode)
Select "Configuration" Go
Select "Maintenance" Go
Select "Roles" Go
N.Muisc/CD and N.Radio/Radio selection should be in that menu.
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