The "bead" I spoke about is the little plastic stop that comes with the s-hawk. I have a Cannon rigger haven't had a problem with the stop coming through the pulley. I also used the S-hawk on my friends Penn Riggers. The bead would not fit through the eye at the end of his rigger, but you could easily modify the rigger by drilling out the eye to a slightly larger size r so it would fit.
As for the other question, the stop is a little bead that you weave the downrigger cable though and it allows the s-hawk to descend along the downrigger cable unti it reaches the stop. The stop is very easy to adjust, but also very easy to drop in the water, so it's nice to have a few spares. The stop looks a lot like my friends electric downrigger stop on his Scotty rigger that is used to "tell" the downrigger when the ball is at the surface. On some other brands of riggers, as mention in another post, the rigger senses the surfacing of the ball due to the ground circuit being broke when the ball comes out of the water. ***BearLakeFishGuy***
"Hey, I catcha nudda crisco"