As has been stated many times before, the aircraft in your default flight should be a default FsX plane. Then when you switch to an non-default one all should be well.
OK. Default flight is with default C172. Changed aircraft while in the parking space. However it made no difference. Did not seem to have the flap and gear issue in P3D. Lionheart is cheering right now. Shut off Accufeel in FSX for this aircraft, no difference.