One problem related to headlights has been reported for the 2015 BMW Z4. The most recently reported issues are listed below.
Headlights are pointing directly at the ground within 15-20 feet of the front of the car. Driving at night is almost impossible without the high beams lit. This is a safety hazard as you cannot see far enough down the road to avoid obstacles. This was corrected previously and through normal operation the aiming adjust sensor in the rear keeps flipping over center driving the aim down.