I struggled with this one big time but managed to push through it.

The pattern brush feature is awesome once you understand how to go about creating the inner and outer corners.  I absolutely love the blend tool.  Now for the transform tool, that is a different story.  I got totally confused on which reference point to set before moving things around, guess that will come with more practice. 

Mahalo Helen for teaching this complex tutorial which I know will come in handy once it all starts to click in :D