I don't have a Killer Kaos kit, but I have built many aircraft. Have a Kaos 40 right now.

Sheer webs add so little weight and so much strength that it makes sense to put them in every rib bay. Cut them to fit exactly between the spars (make an "I" beam) and to butt up against each rib. Glue all around. The wood grain should be vertical. 1/8" sheet balsa is plenty for this application. I've used this method in hi-start sailplanes and have never folded a wing. I add them to all planes whether the plans call for them or not. Cheap insurance! It's a little work, but well worth the effort.

Dave