wierd electrical symptoms? any idea?

[srdiamond]

I have had similar issues on my 2000 4.4 X5 with 80k miles. A month ago strange things started happening. Check engine light came one intermittently. That seems to have fixed itself. Now when I first start the car, almost always the airbag light and seat belt light comes on and stays on. The steering wheel controls (volume, horn, etc) are all disabled while that airbag light is on. If I will simply turn the car off and restart it, all seems OK. Also the Nav screen is staying dark now for a few minutes after I start the car lately. These electrical gremlins are really scaring me. Oh and to top if off, a few weeks ago, I was introduced to the "trans fail safe mode". Now that was scary as the car felt like it was stuck in 3rd gear. I turned off the car and prayed and I have not seen it since. Just so everyone knows, the alternator was replaced 6 months ago and the battery was just replaced this week. Does anyone have any ideas where to start with these weird problems. I don't know how I can even sell the car acting like this?