I never even bothered with the piece of outer cable and just ran the wire across the bracket shell. The outer cable is just a place for grit and muck to congregate.
Regarding chain rub, try adjusting the angle of the changer relative to the rings. Rotate it slightly on the seat tube and/or slightly 'tweak' the inside front edge a tad closer to the ring so that it helps the chain across a bit better. Shouldn't be any crank rub if you experiment although in saying that, my Campag cranks always had a mark on the inside!
Today is the yesterday of tomorrow.