Wonder if you've had rodents in the car while it's been sat semi stationery, could explain random electrical issues.
Sounds like its near on fixed now though but I've only skim-read the thread..
This bits more an FYI than anything else as I see you mentioned the car turning over back at the starts, If the battery was on its way out, or even just not being charged by the alternator, just because a car turns over doesn't mean there's enough juice in the battery for everything else, there's so many controllers and **** these days that might not be happy when you're trying to run a starter motor and power pumps and control modules, get a new battery on a car, make sure its putting out enough juice, and then clear all the fault codes and see what comes back after an hour..