Great choice.
Yes you'll be able to use the HD Recorder and the STB, if you are able to control then with the Beo4 in the main room.
From the link TV, you'll not be able to see the grey menu that appears when you are on the STC-C, but you'll be able to use the commands with the Go button. Go 1 = Menu 1
In term of cables, you'll need a masterlink cable and an areal cable. You'll also need a RF amplifier that you buy from B&O.