Great game! I found it quite interesting, although I spent most of the time looking for the book (which was too well hidden). I also noticed a couple of bugs that didn't hinder my experience much but did make me laugh (the player loses stamina while standing still and holding the shift key, or accidentally climbing some trees, giving a good view of the map).
And I got a good scare with the deer, and also at the final part when all the candles were lit (the sound almost gave me a heart attack). Great job, Niven!