I liked this a lot! It was a fun read and has a lot of gonzo stuff going on. Who doesn't love weather Wizards and mysterious subterranean creatures?
I also thought the layout was workable and the map very legible.
I feel like tying a solid idea for the crystal would really strengthen the module! I want to know what YOUR vision for the trek up with the crystal looks like, because a GM will homebrew it anyway. Maybe even a table, with effects: Big crystal, takes two players. Bright crystal, effects stealth, etc etc.
In keeping with that idea, in a module I would pick up to run, I think I'd want more exact amounts for how much food is in the crates an barrels in room 2. Just to lower prep overhead.
I think you did a great job with the space, there's a lot here to play with!