i think you've got a second or two to mash the buttons after connecting the battery, probably while it's still displaying the firmware info etc before it's got to the safe screen
here's our attempt - not going to win anything, 1/046kg lifted, best so far seems to be about 2.8kg, but we had fun trying ! Narrowly averted entry to the disaster category...
yikes ! Firstly, take your props off until you've got this sorted !
I'd check in the receiver test menu. Yaw, roll and pitch should all read zero when the stick is centered and +/-100 at full travel - especially yaw since that's used for arming and disarming. You may need to change the...
don't know I'm afraid. You could measure it with a multimeter, see if you get the same voltage readings. You could also measure the current draw if you connect it that way, but I assume that'd be tiny
I've got mine as just a wire from the positive terminal on the kk board (don't need anything on the -ve terminal) connected to the positive on my pdb (ie to the positive main battery wire). I've got it set to 108. Works fine.