dangerous door lock problem

Post #1 My wife called me at work today frantic because our 11 month old was locked in the van. We've been having problems with the doors unlocking/locking by themselves with either the engine running or off and vehicle stopped or moving. The problem has gotten steadily worse in the last week. She put the kid in the van and started it up to get the a/c going and closed his sliding door. She then put the stroller in the back and closed the liftgate. Immediately the doors locked with the kid inside. After I called the cops to get it open she called me back and said they unlocked by themselves. I pulled the 40 amp door lock/seat fuse under the hood when I got home and all he** broke loose. The ABS and airbag lights came on and the blinkers and the heater fan motor wouldn't work. I located a used BCM for $35.00 so I think I'll put that in tomorrow. Any tricks to doing that job without causing a major electrical problem? This van might get a bullet between it's headlights.