I need to know what the running temperature is

Replace your radiator cap, it is dead.

Also, check your sensor as it may be broken. Its plugged on the bottom of the reservoir. And while you are at it, check the reservoir, as the system set up by BMW consist of the same mechanics in a toilet tank (sorry to be bold). there is a small plastic thing that lets a hollow (i believe) plastic (cylinder move freely up and down) this is what controls the message on your computer screen in front of the shifter.