Hi T,Elevator and ailerons are terms for fixed wings aircaft, nick and roll are mostly used for rotorcrafts.
Why do you need calculate lift angle? Your copter does not fly that way, if you elevate copters nose you will fly backwards, unless you fly with high speed.
The lift angle is the angle the REMOTE should travel to get from 0,0,0, to 7.8 forward and 3 higher. This is nothing to do with the angle of the REMOTE. The REMOTE will tilt front down to go forward as usual, and speed the props up to go upward, so as the get to the end of the orange 'H'.
Do you understand, I can explain better.
C.