1) Dry, threads greased.
2)Sometimes I pop a primer. Whether or not I do, I leave the gun loaded for a couple few days.
3) I just use rem-oil. Any good gun oil will work.
4) I use foaming bore cleaner in my centerfires frequently. Just oil afterwards.
5) Put some lube on your pinky or a q-tip and rub it around. You just need a little bit as extra insurance up front.
6) Dunno that one..