Electrical starting system shutdown-could be nuclear meltdown

[Dave2]

I'm in the process of diagnosing what initially appeared to be a dead cell in a battery on my 1992. The car battery was on a battery maintainer (green condition light on). I had plans to start the engine and service the vehicle for spring. When I got in the car, I had no interior lights, and a strange clicking from the PS dash. Pulling the LCD fuse would stop it. Replacing the fuse, I attempted to start the car and that was the point the dead cell in the battery was discovered (10v). So much for the green light on the maintainer. I replaced the battery. I reattempted starting the car and discovered: no starter engagement, still had no interior lights, dash LED, no security indicator, or door chime. Headlight are nice and bright. I re-tried starting the engine 24 hrs later (assuming there was a timer) with the same results. I'm not sure what components could have been damaged in a prolonged low voltage situation. I have had suggestions this may be VATS related. Where should I start on diagnosing this?