Hey There.
I also have the PFC boost control.
The way it works is that the 0.8,8,9,1.0 Bar settings sets the max HELD boost. You will find that no matter what the other setting is, on sustained full throttle, the boost kit will hold at that boost.
It may spike however if the duty cycle is too high a number, which will bring boost on really fast, it will spike and then settle down to the max boost number.
The 255 bit, is a non user adjustable display. When you change the max boost number, this goes back to 255. Once the PFC has learnt how to control the set amount of boost, this number will change to a different number, which is simply a display number. You cannot adjust this.
You should asjust the gain so that you don't spike the boost. You can check this by watching the line graph whilst ramping through the boost.
BASS OUT