Simultaneous codes & warnings. Solution?

I recently got the "trans failsafe prog" message, then the tach went crazy, speedometer and temperature guages went crazy. Autozone diagnosed battery as ok. Independent (BMW diagnostic) guy said battery was ok. Possible causes were too numerous to believe that all had merit. Car would drive in limp home mode. Finally after sitting a few days, it wouldn't start. I took the battery out and went to get it tested at a different shop and it read "dead". So I bought a new battery 1000A 860CCA 150 reserve. I expected to be able to start the car, but it would not start. The starter doesn't seem to actually click in. I have to wonder if there is a lock-out occuring. Perhaps an anti-theft or some other code that needs to be reset.
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Just days before this showed its ugly head, I had a shop diagnose a power steering leak. It turns out that it was simply a hose ($265 for the hose alone). However, to diagnose that, they cleaned the power steering hoses with water. I'm afraid that the water may have ruined something nearby and started all of this.

Right now, I just have to figure out what is preventing it from starting. Any ideas?

Thanks for all the input. This is helpful.

Any codes? Possible crank position sensor, but normally when you get the 'transmission failsafe' message, and your car has been running all right, it is the battery at fault.

Any warning lights, eg: SES light?

jake

thank you. I did replace the battery, but it would not start. Before battery replacement one mechanic wanted to replace the DSC ( he thought the battery was good). I am waiting to get new reading on codes.