grand voyager problems with the power doors and whistling sound when engines stopped

Hi i really hope someone can help, i have recently bought a 51 plate
chrysler grand voyager.
the o/s power sliding door will occasionally attempt to open when either
the button on the fob is pushed or the button inside the car is pushed,
you can hear the motor working it will release the lock but fail to do
anything else, if you then manually open the door, then push the fob
button or interior button the door will slide close and shut itself.
the n/s power door and boot are just as tempramental they will rarely
open from the keyless fob, i therefore changed the batteries yesterday,but
again still no joy, the n/s door will allways open from the interior
button,but occasionally from the fob??
the power boot sometimes tries to open it will unlock but fail to lift
from either the fob button or interior button.
once the cars stationary and the ignitions off after my wifes home from
the school run a high pitched whistling sound can be heard for around 3
minutes then it stops,could this be the turbo cooling down??
the n/s mirror fails to power shut, it does a full 180 degrees and keeps
moving backwards and forwards??
finally the car has no owners manual, and im trying to work out the alarm
system it seems if i push the lock button 3 times the lights flash and the
alarm sounds, am i to assume thats activated it??
thank goodness the car has warranty,i will be intouch with a list later
on.
please anyone who can help it would be much appreceiated.
steve