First of all, I think this level has to be removed, because it uses music from Shadow of the Colossus, and I'm pretty sure that you are not allowed to use it as you wish. I may be wrong, but someone who knows more about it look at it please.
I always have a hard time understanding why ever level gets such a warming reception in this community, I guess it is what makes it unique. Because lordmarzog said pretty much what I would say, except I would curse a lot more.
It really blows my mind at how this had 2 betas and a final version and still feels so unfinished. What the hell happened in the begining cutscenes? There are 2 versions of them and they are both broken.
There are WAY too many invisible death objects, tiles that are used simultaneously in the background and as solid tiles, tiles that all of a sudden kill you. Lots and lots of voids and wallswims, even when trying to follow the main path. The player is made to follow a very, very strict path, or else everything breaks. There are some essential invisible shifts that can be completely avoided, and the player has to realize they are there in order for things to work.
And that boss... how was I supposed to guess where I had to hit him?
The only thing I can think was good in this level was the atmosphere, that was actually very good. Also, I don't usually play Knytt Stories levels but for some reason I had to finish this one, maybe thats a good thing
I'm sorry if I'm being a bit harsh, it just feels like you never played through your own level. If you ever decide to make another one, try to test it a bit every time you do something new, and this forum is here to help, everyone likes helping new level makers, you can always make a level preview thread and ask for people to volunteer so you can send them the betas, works much better that way
Don't give up, you've got the creativity and that's one of the most important qualities here.