i am so excited! now i know what i'll be doing through the winter. haha. just a few weeks ago we looked at Koka Ninja House. of the Koga-ryu school. it has some of the secret passages. it explains it very well, I think. (in the English section, menu is called Notes)
i love all the little details! (also i'm glad someone remembers that warriors have to eat and drink.) it's like you read my mind. cheers and good luck!