Spirit System

I followed the instructions - Set the Throttle Hold curve to 12%, Lowered the Throttle Range to 1070 so that in Throttle Hold the blades stop spinning. Reset everything. Spooled up, clicked Throttle Hold, and the blades kept spinning. They did not slow down. So I recalibrated the esc. Was I supposed to do that? It's not in the instructions.

Now, today, I put it into throttle hold and it kept running at about 300 rpm - not zero. Very weird. What up?

The ESC shouldn't be recalicated. You might need to decrease Throttle Range - Min. even more until it will stop spinning.