Very good
Lots in here. It all seems all right to me, except it is poorly written, filled with typos etc. Music would have been good, or just a few sounds when you click things, anything to give it more life. Take a look at my Art tutorial- it is probalby not as well presented as yours, nor anything like as informative or technical, but the voice makes it stand out. Our NG Expert tutorial explores the full range of music and sounds, bringing life to an otherwise boring subject.
If you ever want to do a full resub of this, let me know and I will edit the text in full and correct your notes too!