but I have a problem with my Xenon headlights. The old Xenon headlights' lenses used to automatically adjust ( move up and down ) when turning the lights on. The new lenses don't move at all when turning the lights on. Why is that? In addition, the new Xenon headlights are manufactured by HELLA and not BOSCH, any diffrences between them as I find that the color of my Xenon beam is more Blue than original BMW headlights.

I believe the self-leveling system was updated in Model Year 1999 to run on the K BUS system of the car.

The older, 1997 light was the older "analog" connection to the system. You may also need to update your LCM (Light Control Module) to LCM III which was phased into production on the 1999 M.Y. If you do replace the LCM, the new one will need to be coded by a BMW dealer or else you will have inaccurate mileage on your car, and the "manipulation dot" will illumiate next to your trip meter. The color is simply related to having an older bulb, or a bulb from a different manufacturer. For instance, when BMW used Osram bulbs, the beam is a more purple/blue color. Whereas, a Philips bulb is a more whitish blue.