Hey there skipper :D
Overall a great tutorial, the explanations were complete and concise, tellikng us what do do and how it works, brilliant explanataions of complicated things.
I only saw 2 bugs; if you keep holding the ball and drag it to the side of a bit of the terrain, and keep dragging it into it, when you get the ball out of the terrain there is quite a bit of distance between the ball and the cursor. Another thing was that the ball sometimes hopped up a pixel repeatedly after a few bounces, but most likely can be fixed by changing a few variables.
The menu and navigation buttons were simple but effective and it was nice and straightforward to whizz around the tutorial frames easily, though the text could get a little bit small on some buttons. One more thing is that you maybe should've added a rectangle or something in the hit frame of your menu buttons, as you have to exactly click the text to get to different parts.
To sum up your tutorial in a few words, I'd call it fine and dandy, nice job.