It's FIXED finally!
Well, the instrument cluster has been replaced. It is the 2001 style, making me wonder if the cluster they put in the 2000 CL's and S's are defective or troublesome. Anway, I am just glad it functions correctly and it appears so far that it was installed correctly. Will know more when I detail the interior.
They also replaced the fuel pump, which I guess was defective. So no more humming noise.
Now, I wait and see if the car behaves. If not, then I have my eyes on the new mid-size Bentley that will be here in 2 years. :-)