More specifically, the level requirements, for quests like Boethiah's Proving or the Ebony Warrior quest. Just starting with Construction Kit, tried looking at tutorials on wiki, but nothing I could locate on level reqs, so figured I'd ask here. Any help would be appreciated.

Have you tried GetLevel?

http://www.creationkit.com/GetLevel_-_Actor

You should be able to do an if, check the player's level and only let the quest advance that way. I haven't used it but in theory that should work.