My players are loving this adventure so far! Using the alternate plot suggestions in the module, I've implied that Treona may not be wanting to acquire the Slaying Stone for altruistic reasons, and that she and Dreus were contemporaries in some sort of wizard training. Also, rather than having Kiris Hoyt's problems be a family affliction, I tied his story to being punished by Dreus for some rude remarks and advances.
We're pretty far through the encounters, and I anticipate the PCs confronting Tyristys next session.
I think this is the best low-level module for 4e I've read or run, but it could use some more suggestions about how to handle the situation if the PCs choose to attack Tyristys rather than negotiate. Since I'm pretty sure at least one of my player's is planning on a fight, I'm going to set her level at or just above the maximum they should be able to handle at their level (say level 6 - 8) But I'm going to offer broad hints that they will be out of their depth should they choose the path of violence.