2002 Ford Explorer Door Locks/Interior Lights/Auto Lamps/Re

My 2002 Explorer just went off the deep end one day, with doors locking and unlocking on their own, the auto lamps, interior lights and accessory delay do not work correctly. It's like the car doesn't see the doors ajar. (The door ajar light doesn't come on when the doors' are open.)

The mysterious unlocking / locking stopped after the battery went dead because I left the lights on. (Still accustomed to auto lamps) Anyway, they work fine, except the rear hatch won't open at all.

There is a static-type sound coming from behind the C-pillar panel. I was told that there is a control module back there and that it controls the items I'm having problems with.

I really would like to have a second opinion on this or perhaps some trouble-shooting tips before I make an investment.

If this is the problem, I also need to know if this can be a DIY repair or is there some programming involved from the dealer?

Some other background info includes:
Aftermarket stereo, Viper alarm w/remote. The factory is supposed to be disabled.

Everything worked fine until about a week after the stereo went in. (Pioneer CD/Navigation)

Any help will be greatly appreciated.