. . . That one needs to be a castellated nut, IMHO.
I agree, Kevin. Nylocs are good at applying tension in a tight joint, but not as good at resisting rotation in a loose joint.
I talked to Scott at the factory. He said that, on his own flap cable attach system, he used an AN3-12 (drilled) bolt with a castle nut and cotter pin. I recommended that they change the manual and BOM to include those parts, and I'll use them on mine, too.
I think if I was already flying mine, I'd look at your experience and replace those parts at annual or even sooner, since they're accessible.
. . . Also, on a related note, why do they specifically call for a nyloc on the elevator bellcrank? As important as that is, and the fact that it rotates should necessitate a castle nut with cotter pin.
The elevator bellcrank is
mounted to the fuselage attach point with a drilled bolt and castle nut with cotter pin. The bolt should be greased.
But the control rods attach to the bellcrank using undrilled bolts and nyloc nuts. Scott said that's because the bolt and nyloc nut are supposed to hold the fork tightly onto the inner race of the bearing and lock it in place. All the rotation is supposed to be in the bearing itself.
That makes sense to me, so I'm okay with using nylocs there.