Shimano Flightdeck computer troubleshooting help

I'm trying to still use the Flightdeck system on both of my road bikes. The 3 x 9 bike is functioning pretty well although I'm always mystified why the display won't stay on the data selected - it wants to auto toggle to the next stat with no apparent input from me.

Then there is my 2 x 10 Dura Ace 7800 bike. The Flightdeck on that one is really not set up well at all. For one it thinks it is in the big chainring all the time. I tried once to reset the left shifter wiring harness by bending it out slightly then inserting a small piece of thin cardboard behind it so that it is fully engaging the electrical contacts. I also sprayed contact cleaner on a Q-tip. These things haven't made much difference. I don't have the Shimano hoods anymore, instead I am using "Hudz" replacement hoods. I am beginning wonder if perhaps the rubber nubs on the inside of these that are supposed to engage the small buttons on the 7800 integrated shift levers perhaps are not engaging quite right.

Anyway, I am posting this on the classic and vintage because the 9 and 10 speed era of Dura Ace and Ultegra parts are no longer contemporary, going on 20 year obsolete tech. A few years ago when I googled for troubleshooting advice I was able to find a lot of useful information. Now for some reason, not so much.

So, if you happen to know of a link to a good set up video or old thread discussing troubleshooting these funky bike computers from Shimano, do share!