Who is to blame when a parked uninsured car being cleaned opens the door and is hit by a car that had stopped in the middle of road to let out passenger and sets off without warning?

If your the uninsured car was parked, and the door was already open when it was struck, then it would be the other drivers fault. If you are parked then you are classified as a permanent object, and you are treated just like all other permanent objects such as trees and signs. The other driver must have control of his vehicle at all times, and by hitting you while you were stationary and not moving, this was not the case, so he is At Fault. Now if he was driving and you opened the door right as he was passing you, then the answer would not be as clear cut.