Haven't read through your whole post yet, but wanted to comment thus:

when i pulled it while playing,

Popping when you pull it while playing is normal and can't be avoided.

i also had a problem that the player state was not being saved. at any time. or, it seemed to get saved randomly.

That does indicate a problem, check fuses as Hugo said.

I'll go read the rest of the posts now. Your wiring diagram looks correct, by the way.

Edit: I see the second thing was solved after you wired it correctly, but you've still got the odd bang when you go from ACC to off, which is still a problem.