Hi Dave
The Masterlink manual is very useful and full of loads of information but you do need to get your head around the terminology.
Perhaps I can explain it this way:
Option0 = No response to any remote commands
Option1 = Main products only respond to like minded commands. i.e. BeoSound products only respond to audio commands and BeoVision products only respond to Video commands. This is the factory default and if you do connect an audio and video product together you have to add "AV" to the list button of your Beo4.
Option2 = Main products respond to audio AND video commands. i.e. Speakers connected to a TV means the TV should be in Option 2 and the audio (with no speakers connected) should be Option 0. You now don't need to use AV as there is no clash.
Once you have these options clear then simply think about their link room versions.
Option5 = Same as option1 but in a link room.
Option6 = Same as option2 but in a link room.
Option4 = A special "LINK" option where you may have two remote sensors that can both see your remote at the same time. i.e. A Beolab3500 and a BeoVision6 both in the bedroom. One in option6 operates as above, the other in option4 only responds when "Link" is added to the list button on Beo4.
I hope that the above clears up the confusion and doesn't add to it.
This is what Christmas is all about, the wife wrapping presents and me whittering on about option programming.
Merry Christmas to all fellow BeoWorlders and keep thinking positive thoughts for 2009.
Best regards
Opman