Fail to start up PV2+ in Naza mode

[AAC]

When I was in Phantom Mode, I pressed Left stick to right corner and Right stick to left corner at the same time to start the motor.
Yesterday, I switched to Naza mode. It was able to fly in auto-pilot waypoints mode, it took off and landed automatically. But when I tried to practice CL flight under GPS (S2 in middle), S1 in top position), I was not able to start up the drone. I tried to move sticks to different corner combination but no luck. I checked the manual but didn't find any tips.
Help please

 

[Damon]

Try starting with both in up position letting it initialize and set home point and course lock. Flip S2 to middle CL once your in the air.

 

[4wd]

You might check calibration of the sticks, worth doing whenever you change anything and have the software connected, it only takes a minute.