I've been playing this hack recently, and I've found that there are a lot of levels where it seems that I can't find 5 Yoshi coins, but when I checked for them in Lunar Magic, in most cases it turns out that the Item Memory Index for every sublevel of a level is left at 0, so collecting coins in the same X position as a Yoshi coin in a later sublevel will cause the Yoshi coin to not appear.
This is particularly blatant in the level Special Scary, because there's a spot where the player will naturally stand at the very start of the level within a Boo Ring with a coin that happens to be in the same X position as a Yoshi coin at the start of the second half of the level. So, a player that doesn't know to avoid that one coin at the start (which is tricky because of the small platforms and the Boo Ring) will have no chance to get the Yoshi coin at the start of the second half.
This issues can be fixed by making sure each sublevel is set to a different Item Memory Index, or by setting them to "Index 3 (No Track)" for sublevels that the player can't revisit.
EDIT: Oh, and in the level Scary Storage, it is impossible to collect more than 2 Yoshi coins, because the Yoshi coins in each of the first four rooms are all in the exact same position, so when you grab one of them, they all vanish, with only the Yoshi coin in the fifth room remaining since it's in a different position.
Oh, and one other thing to mention: Near the bottom of the level Scary Tree, there are some damaging floor tiles. Those are okay, because they look harmful, so the player knows to avoid them. However, up near the top of the level, there is a nearly invisible tile (consisting of faint green lines that almost exactly match the background color) above one of the vine-topping blocks that hurts the player. Why is that even there? In addition, the vine-topping square blocks on the secret exit's screen are all harmful as well for no good reason. Why were they set to behave like munchers/spikes?
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 =^.^=