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.
I really enjoyed playing it. The overworld is very well thought and levels are the same, with some of them being hard but totally goalable without using savestates. I figured out to find all 93 exits without having any problem.
A special mention for musics which are very pleasant to listen, a very nice tribute to DKC and Zelda... and being a Zelda fan it was a very good surprise =^.^=