Disclaimer: Not an EE, in no way am I nearly as qualified as the folks who have already responded.
My $0.02 is: My dad (Nuclear Physicist) always told me that whenever something is "screwy" with your electrical circuit (trailer lights for the boat, Legacy signals ?), look for some kind of ground/common fault. I have always found this to be true.
So I mean no disrespect when I ask: Is "common" common throughout (For instance, is the TMCC "common" the same as the Legacy "common" for power, etc.)? I have had a lot of wiring issues with common (much smaller layout [who's isn't!] but three loop layout) and still had switches work, etc. It just seemed that there was always "a place that things didn't work well" which, ultimately, I traced to not have common wires "common" (i.e. "ground").
Just trying to help...
Bruce
