Dammit, I am kicking myself at the missed opportunity to hyperlink to the Black Sword Hack SRD. Super big brain move that meant you didn't need to list all those tiresome page references.
I legit love the whole framework of this scenario and I think that when I run Vaults of Vaarn, I'll likely use this adventure to bring it to the table. It's one of the more effective ways of implementing a time loop I've seen and I like the despair mechanism that makes the looping finite. Very clever!
You've crammed this thing full of science fantasy and I adore the injured time traveller. Wish you'd had room for a little easter egg reference in naming him, but he's a standout feature nonetheless.
The visuals are fab. 100% nailing the Vaarn vibe and evoking a blue desert that gives you the blues! The hexflower with the keys around it is a genius piece of layout and design. Another one I'm jealous of not thinking of.
Really nicely done, sir.