Congratulations on your purchase! Here ya go:
1. Sounds like the actuator is leaking. Either replace the actuator in the door, or just cap off the line to that door and live with a door that won't unlock. Could also be just a leaky line. Chasing the leak down with a hand vacuum pump like a MityVac can be an experience.
2. Harsh shift may or may not be related to the vacuum issue. If the shift improves after fixing the leak then your okay. If not there is plenty of info on this board about adjusting MB transmissions.
3. Make sure the boost line to the ALDA is clear. They clog up with soot over time. Do a search.
4. Check the fuses, could be a wiring issue.
5. If you don't know about suspensions have an indy MB shop check it out and show you what is wrong. May be cheap, may be mega-$$$ but once its fixed they last a long time.
RT

__________________
When all else fails, vote from the rooftops!
84' Mercedes Benz 300D Anthracite/black, 171K
03' Volkswagen Jetta TDI blue/black, 93K
93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K