About 2)
With auto-throttle engage, the N1 button will iluminated when the aircraft reach the reduced thrust altitude that you put on the FMC.
-So, you take off:
A) You push TOGA
B) N1 and TOGA are shown on the Flight Mode Annunciator.
C) At 80 kts, you will see THR HOLD, instead of N1 in the FMA.
D) Them you will see ARM instead of TRH HOLD in the FMA.
E) At reduced thrust altitude, you will see N1 again in the FMA and will also iluminate the N1 switch. And you will also see CLB in the Thrust Mode Annunciator.
You can also set the climb thrust value manually (with auto-throttle disengage) that figure at the N1 limit page (CLB) by switching L4 from the CDU.
I hope it helps you!