I doubt we'll ever get something like that. I'd love a Dungeon and Wilderness Exploration Guide that expands exploration, or an encounter guide that spends time on how to do social encounters. Honestly, though, I feel like I'm usually stealing scene rules from other games most of the time.
The puzzles section is basically a dozen or so example puzzle encounters. I remember the first one being labelled "easy" and I thought it was the hardest one of the bunch. My group isn't really into the kind of puzzles they present. They're the kind where you'll have a word puzzle on the wall or a chess board on a pedestal. Those don't work well at my table. They're fine, but 3.5e's Book of Challenges is much better, IMO.