So, I've played this one and found it to be pretty enjoyable. I feel that it does a good job of emulating the old Z1-esque format, while still giving it some of it's own flavor. I found the 1st dungeon to be pretty clever with how the moldorms are introduced, and then you return back to them able to handle them.
One of the big complaints I've heard is dealing with Farore's Wind, but I love the idea of an in-game escape tool. I would actually suggest maybe moving it to EX1, or another additional button, to prevent players from accidentally using it when they don't want to, but still giving them a means to escape. You could even then tie in that ability to "quick escape" into other mechanics later on. Maybe death traps or such? Just throwing it out there.
I saw some people complaining about the staircase to the L1 item, but I know personally I had no issue with it. Again, it felt deliberately old school and since there's not a ton of rooms where you have blocks in them, I think it's fine.
The boomerang's re-purpose is quite nice, honestly. It kind of ties in with the more modern Zelda games where the boomerang functions quite well as a weapon.
This quest, while short, has a ton of potential. I'm really curious to see where it goes. I'd give the demo a 5/5 overall, since I found no issues and it definitely interested me in seeing more. I would recommend maybe you should consider opening up a quest project, so people can continue to follow this after the Expo. Good luck!