I have no clue as to you radio issue.
As to your locking issue I would look at a couple of things when you lock/unlock the door with a key it closes a circuit which starts the vacuum/ pressure pump under the pass. rear seat and unlocks all the doors trunk and fuel door. The same should happen if you unlock/lock the trunkwith a key. Since your remote switches it is probably sending a signal to the pump, but the pump is not reacting. There is a tool called a mighty vac which creates vacuum if you need to troubleshoot lines or actuators ($50). I think it is vacuum to lock, pressure to lock. I bet your lumbar support does not work either, since the pressure comes from the same pump along with the handle. There might be a problem with fuses, or a vacuum leak which could cause the pump to turn off due to the safety cicuit built in. Take out the seat and see if any sounds come out of it after pulling the fuse for a few seconds to reset. I think there was a note from MB that identified a problem with a bad hose inside the pump on 95s, which can be replaced if the pump attemps to run but can not develop any pressure or vacuum.
I am confused why you cant get the drivers door button to go up or down with the key, the switch on the inside is very similar to the remote in locking unlocking (starting the pump)