Not sure what you are asking.
F Mode is Idle up or Stunt.
You should not be trying to start up in that mode, the slow start of the ESC could be kicking in if you tried to start in that mode or switched too soon.
Just stay in Normal mode until you get things figured out.

I'm not sure why the rudder travel adjust comes set at 90% in both directions. But it will control the piro rate of the heli and might be set at 90% to eliminate binding at both end of the tail servo travel.