First thing about the set speed function, would be to set the accel rate to the #1 so that the engine does not appear to jump to a high speed setting. Even if you don't change it, knowing that the engine adjusts quickly, I'd recommend using a couple of steps to get up to full track speed. Set the engine at 15 MPH for example and then another setting like 25 MPH.
The PFA sequence is activated by pressing the PFA button, and then the red direction button after you hear the bell start ringing and when you wish the engine to stop, or play the next sound sequence. It will accelerate at the end to the last speed the engine was at before you pressed the PFA. So again use the accel rate to change just how fast the engine goes up to that speed or slow the engine before pressing the PFA!
