Thanks.

2 - I will check, but I'm pretty sure when I turn it off rolling it just rolls to a stop, there's no power to the motors. The weapon is activated fast, I couldn't check it in the same way but I suppose it's not needed if the other test shows the failsafe is OK? As both systems get their signal from the same receiver?
3 - so between the tank and regulator, I need a prv rated to 1000psi?
4 - I am using a 5/2 solenoid. So 1 prv between the regulator and solenoid would cover the lower pressure section I think?