I haven't read the annotations, so I'm not sure if these questions were answered there or not. (Feel free to throw one at me, if they have been.)
1. A Returned will only live for a week, unless said Returned is given a Breath. This is an important part of life in Hallandren. I assume that their "biology" is set to consume a non-Divine Breath if one is available, and their Divine Breath if no other Breath is available.
1a. Is a breath slowly consumed over the course of a week? Or is it consumed all at once, granting a Returned's body one more week of animation? If the former, and a Returned is consuming its DB, will the DB regenerate if a non-DB is given to it? If the latter, what happens near the end of the week if a non-DB is given? Do they stop being Returned, since the DB was consumed, or does the DB "magically" return to the Returned?
1b. (This actually bothered me as I was reading the story.) What's the population of Hallandren? I mean, this Breath-consuming religion of theirs has been around for how long? And they've had how many Returned? With each one living for how long? Yeah, that's a lot of Breaths that have been sacrificed for their gods. I'm surprised they haven't run out.
2. I may be mis-remembering this, but didn't Vasher say he had existed without Breaths before? How is this possible? He's a Returned, right? (And didn't Denth say something similar?)