Has anyone figured out a throttle kill for 350qx?

I'm new to all this custom programming and kinda new to the world of flying. I have found I love my Devo 8s but the BLADE 530 qx program doesn't have a real throttle kill. If I move the trim to -110 it will kill the props but is a slow process. I can also hit the RTH switch and it will kill the props but again is slow.. I would like to use the ELEV or AILE switch to kill the props. Is there any way to make of of them (when switched) just put out -110 throttle? I think this might work as a kill switch. If I set my throttle to -110 at the lower limit my props will never arm. I know I should mess around with it but i'm afraid if i mess around too much I'll totally mess up base "map"

If I adjust that the motors will never arm. Anything below 100 and they wont spin up..

Sorry that's what I meant to say if I go to 110 or 125 they won't spin up BUT you got me thinking and I figured it out. I increased the "safety" value (that appears to be associated with the throttle hold) to -110%. Now when I flip the RUD0 switch to 0 it kills the props. When I flip it to 1 it starts the props.