Can a ranged Conductive weapon (i.e. Crossbow) be used to deliver a special ability requiring a melee touch attack?
For example, an Antipaladin channeling Touch of Corruption through a Longbow.
I'm inclined to say no due to the "appropriate type" clause, but I'm not 100% certain that's what it means.
Nope. Conductive melee weapons deliver melee touch attacks only, conductive ranged weapons deliver ranged touch attacks only.