Tip: You can use Lunar Magic's Overworld Layer 3 Editing system to edit or create your own layer 3 images (castle bricks, fish, rocks) and apply unique effects per level via the Layer 3 Bypass in the main editor.
Really sweet demo. I absolutely love non-linearity in overworlds and this is a great example of that! Though I feel the switch palace paths sometimes get a bit too long, to the point they can be mistaken by actual progress paths. Maybe something worth looking into.
Don't know what else I could add from Erik's old review.
Oh, if you're doing proofreading you might want to fix the hub level's name, it's spelled Hut and not Hutt lol