Hi Stephen.
Obviously the signal will be poor if you use so many converters. However, I would suggest that you use the Scart option or the triple Red, Yellow and white cables(VGA). Of course in such a test I would also unplug all devices.
Your N-Music and n-Radio will work definetelly over the link.
Another stupid question but just to ask. Do you have it linked? I mean do you use the ML connection on BM1? Also you should disconnect the Beoport in such a case. Frankly spoken I think Beoport is not much of a use if you have a Beomedia1. But your choice...
I'm pretty much sure that on V.Aux (If BM1 linked) should work. All other sources from your Video Master are being distributed in the rest of your link TVs? e.g. DVD, SAT Rx, VTape etc? Also do you have the iR eye connected? If it's linked I think you do not need to use it due to double commands.
I'm sure we will finally come to a good result. It's only a matter of time some effort and many many tests!!!!!!!!
Regards
Spiros