The aux cooling fan usually comes on first for A/C reasons. If the A/C is off and the car has just started and the fan is on then yes you probably have a relay problem. Get a wiring diagram and check it out. Your tech should not have problems with testing this.
Did you replace the accumulators on your suspension. These are the cause of most leveling system problems. If you are low in the rear then the system is not pumped up. Again your tech should be able to diagnose these problems or you might look for another.
The system will level the car if it is working properly. It will make up for weak springs as it will a heavy load. Thats the point. There are no alignment adjustments in the rear suspension. It should be in alignment when the car is at the right height. Getting the ride height right doesn't necessarily require testing alignment.
MB has very large dogs on their parking pawl. This means that they will roll much further than most trannies before they catch. They should not miss a tooth though. There are conditions where the pawl skips or misses a tooth. A simple evaluation by an experienced tech should be all thats needed to verify either condition.
Bosch Master, ASE Master, L1
33 years MB technician