1) when you intercept the ILS using the autopilot in a real aircraft, do you have to be descending at the same rate as the glideslope to prevent the lurch downwards that often occurs when selecting APP in a certain Microsoft programme?
2) similarly, can the autopilot turn the aircraft to intercept the localiser accurately without the over-correction that happens in flight simulator?
I don't know anything about microsoft flight simulator, but if the autopilot is flown properly and the airplane is properly configured and prepared for the approach, then the transition should be very smooth. The airplane needs to be configured and on speed, and if the autopilot is engaged, the transition to glideslope capture is often seamless.
If the aircraft is equipped with autothrottle, the pilot needs to ensure that the proper localizer intercept angle is made (too much angle and too much speed leads to an overshoot or a rapid turn, or flying through the localizer), then simply arm the autopilot. If everything is done properly, the aircraft will intercept the localizer, fly to the glideslope intercept point, and reduce power when the glideslope captures. All the pilot need to is lower the landing gear at that stage and apply the final flap setting, if appropriate.
There should be no jerking, or overshooting, if everything is done properly.