I think there will be problem with the communal system,but only in as much that you won't be able to access all the channels.
Your immediate problem may be due to "data collision" via the scart cable.B&O use pin 8 of the scart port to communicate with a compatible B&O.In your case,using a Sony tv may be an initial problem.
Try disconnecting the scart cable,but use the rf connection from the Beosat instead.If the Beosat comes on ok,tune a spare preset of the tv in to view satellite.
If this works,you can then disconnect pin 8 of the scart cable in order to use the direct av connection,for best sound and picture.
There are various ways to adapt the receiver to the dish feed available.
Regards,
Nick