I've only been quilting for four years. I found putting the ribs together a breeze. I did have some trouble with the curved corner pieces, you kind of seam up to a point then applique the rest of the way. If i were to make another I would plan from the beginning to leave enough extra fabric on the top of the ribs to fully applique the corners.
I'd be interested in hearing from the others that have done it how they managed those corner pieces.