Yeah, looks good. Now at the beginning of the tutorial you should explain what the difference between wai/ai files is. Namely that the first one are made in GUI AI editor, whereas the .ai files are JASS-coded with a text editor.
Oh, and we have a rule about color tags. They shouldn't be used because they can hardly be seen on certain forum themes. If you could use italic or bold instead of colors that would be nice.
Other then that i think we can soon approve this. Good work!