Very impressive map I must say. But I don't think the creators had the logical aspect of the entire map design as a priority when they made the game. I didn't think about it when I played it at least, since the immersion, flashback scenes and scares made me lose my sense of direction now and then.
There might be corridors or areas intended between the "area doors" that they didn't bother to put in, for a lack of actual purpose. There are a bunch of locked doors that can't be opened (in the storage, prisons and so on). So we are not given the entire structure of the castle as a player. Also, a lot of the map subsists of secret passages and sewers etc, which would explain the lack of logic in the designs.
Really cool map tough!