The thing I'm stuck on right now is the scene in Ep 5 where ZYL is looking at the Dial and it activates and shows him a picture of the Awl. Is this ever explained? I am considering the possibility that the Hallows are at least semi-sentient, either 4 minds or 1 mind distributed across four objects.

Don't forget china_shop's Very Srs Poll about where the 3-D model of the Dial came from.