Rule 7 doesn't look too dimensional, but it is the tumbling block pattern.
Rule 8 doesn't look too much like a treet to me but it is actually paper-pieced using the Weeping Willow paperpieced pattern from Quilters' Cache by Marcia Hohn.
I am having a little trouble posting. I hope it goes through this time. This mystery has really been a challenge for me, but I have really enjoyed participating in it and looking at everyone's themes and interpretations of the rules. I am also looking forward to seeing everyone's finish and hope we can do this again next year.