Thanks for the reports, some info:
3) Is not really a bug, it is not necessary to loot his corpse and neither do you need the amulet from him. Because he 'story' died and not by the player's hand, there is no loot.
4) The teller is not meant to restock the skillbooks, this was changed on purpose. The books are meant to be unique, 1 time boosts to a single character. It was not intended to have it be restocked.
5) About the blocking NPC's, this is because those NPC's you are naming are performing a script where they are trying to put themselves offstage. The other NPC's where this behavior is not apparent are likely not performing said script, thus will stay in the circle.
