JanieW, I want to make sure you know that your aqua/blue HSTs are turned the opposite way from Bonnie's.
As to the question of whether this is intermediate or advanced, none of Bonnie's units are especially difficult; I think they would be labeled as beginning or intermediate. I think her quilts seem more difficult because of the numbers of units involved, and then the huge amount of info that is released with the last clue.
I would encourage everyone to realize that you can break up this last 'clue' into many smaller ones, and just deal with one a week if that suits. We have until next Halloween to put this together, LOL.