First off, the theme is on point, really. Very atmospheric, with "Where am I" really kicking in perfectly, and the audio quality is amazing.
One thing I noticed tho, is that in "Where am I", the left channel felt slightly louder than the right one to me.
Also, in the Main Theme, the high notes in the piano feel very "over the top" and overrunning the rest. Maybe switching these notes out with another instrument could make a difference.
I liked the wind instrument in the Main Theme at the beginning, it sounds very mysterious and kind of scary. Love it.
The wind sounds and the small wood-cracks in the background were also pretty sweet.
I really liked that harp in the Ending Theme, felt like I was arriving at my home village or something, just returning to a safe, familiar place. Absolutely liked that.
Overall, really nice soundtrack. Well done! Your work is appreciated!