I'm on "The Throat of the World" for the main quest, and when I finally reach the top of the mountain after clearing all the cold wind, Paarthurnax never actually appears. There's no quest marker leading me to anything and nothing happens. I've tried using the console to summon him, but another problem arises when he puts the word for fire breath on the wall. At this point, it's the final word for me, sun. After i learn it I'll use it on him and nothing happens, and he won't talk to me. All he says is "not until introductions are done" or something like that. Can anyone help?