Engine level 8: Castle is useless???

lishogi.org/ft82ybaG/sente
Oh my god!
What's the meaning of castling?
Please tell me where the blunders are......

By the way, I saw my just-played game in the shogi captcha of the forum?????

I feel you castles the wrong side and in the wrong position.

Let me tell you one thing: Keep your king away from your rook. Castles are always build where there isn't your rook. That is as far as I understand - although, I don't have solid proof, just my interpretation - because the bishop is much better at defending than the rook and also constructing the rook into your castle limits his movability.
The castle you wanted to build here is the "attack-me-or-you're-gonna-regret-it"-castle, or so my shogi friend told me. I personally think this castle is connected with more advanced tactics. I personally reccomend going with a mino gakoi or a Yagura. The Mino because it's fast and easy and the Yagura because it's high defensebility. (Yagura only works, if the enemy is also going for static rook! If he does ANYTHING else, your pretty much screwed...)
I learned that building a castle is not always the best idea from the get go if your enemy is playing very aggressively. Your defense can be improvised, it doesn't need to be a distinct castle by the book.
Also, don't build your castle blindy! That is my best tip!

PS.: If I talked nonsense there, feel free to correct me