And about the part "Urine and feces are processed in the thigh pads". Who and how does that get cleaned out, and the smell must be horrible.
The book made it clear that they "stunk to high heaven" when you got close to them. Nose blindness could also be considered a survival mechanism.
I did enjoy the commentary tracks. Since the audio is somewhat muted, that didn't distract from the commentary.
The weirding modules came from a studio note that they needed some sort of "gee whiz" standout bit of tech like the lightsabers for Star Wars. They took the line of the book "I can kill with a word" and made it literal, and fleshed the idea out until the weirding modules were born.
I seem to recall the suits suck all the moisture out of the poop until it's just powder, and then you just open the pouch, and shake the dust out to be blown away in the sands. Everything that makes poop stinky is bacteria, and bacteria die without water, so the powder would probably be odorless. The transition to get there, however...
I thought this movie was perfectly fine... until the end where it rains and presumably kills all the sand worms.