What was the wind direction and speed? With power off, on an approach you shouldn't experience any torque, P-effect, gyro effect, propwash effect - or even hogwash effect. The only thing that might make a difference has been suggested by Bernt Stolle - post #3. i.e. unbalanced fuel tanks.

prop wash

KNRO - you need to fly the aircraft all the way to the ground.. don't expect that one can do a "hands-off" approach every time, as FSX builds some amount of turbulence into the simulation: as well, Active Sky products (and probably REX) also inject some measure of turbulence.

During one of your flights, google "four left turning tendencies" Those will explain why your plane is slowly banking to the left. Try this to really see how power settings and airspeed determine hoe much left turning tendencise you have. - go full throtle and pitch for a speed right above a power-on stall speed.......notice how much right rudder you will need to use inorder to keep the ball centered and to cancel out the left turning tendency...(tourqe) -go full throttle and level the aircraft and see how little if any rudder is needed to cancel out tourqe and the other three forces.