Well, I guess if I was looking for excuse to make a smaller version of our esteemed forum member "JoeP's layout"; this might be it.
Everything was fine except for the sporadic operation of my Lionel R30's doors, until on a far curve in the hardest place to access, on the bottom level tunnel, the R30 set stopped and made a buzzing sound which tripped the Z-1000 breaker.
I crawled painfully underneath that section of the layout; after adjusting two support beams out of the way (never a good thing), and looked around with a flashlight.
No derailment, and no visible obstructions.
I did find a very small and wimpy piece of insulation foam between the rails and removed it, then pushed back the train a bit, restarted power, backed out of the tunnel, and then made about 5 loops with no issues.
On the 6th loop, the same thing happened in the same spot.
So....I think I am going to tear off the top of that 1/3 of the layout, and see what the deal is.
This might be a good opportunity to fix what I feel is a poor design, and maybe add some ideas from JoePs layout.
Moreover, it might be a good time to add those O-54 and O-72 curves as well, to accomodate my new Lionel 28072 Hudson