Overall, I would try to use simpler language. For example, there are more common and simpler terms that could be used instead of the word "aggregate" such as "collection" or "total".
The Stats Page Layout section, I would take out "Let's learn about the Stats Page of Grooper by understanding its layout." from the bulleted list and use that as a text introduction to the numbered instructions.
Number 9 could use a comma after "Kiosk" button. Number 11 could use a comma after the word "window".
In the supademo, on slide 4, the formatting of the text in one of the comment boxes seems a little odd.
The same comma suggestions I had for the text could be applied in the supademo.
