Thanks Mark for your continued help.

I have discovered that the problem at the moment exists with a merged aircraft (SkySpirit 777 ext model with CS VC) and when I load the default 777-200ER GE90B these lights work correctly (:). So, either I not fly the merged bird or I need to do some tinkering with the config, perhaps something getting lost with all the aliasing involved. So thank again.
But now I have another which I am posting in a separate topic.