anchor.diff:  
    (defmethod box-layout-mixin/xically-allocate-space-aux* ((box box-layout-mixin) width height)
      (declare (ignorable width height))
  -   (let ((children (reverse (sheet-enabled-children box))))
  +   (let ((children (reverse (sheet-children box))))
        (with-slots (major-spacing) box
          (let* ((content-srs (mapcar #'(lambda (c) (xically-content-sr** box c)) children))
                 (allot       (mapcar #'ceiling (mapcar #'space-requirement-major content-srs)))
  
positive.code:        ;; now actually layout the children
         (let ((x 0))
           (loop
               for child in (reverse (sheet-enabled-children pane))
               for major in majors
               for minor in minors
               do
  
negative.code:             (compose-space child)) )))
  
   (defmethod box-layout-mixin/xically-compose-space ((pane box-layout-mixin))
     (let ((n (length (sheet-children pane))))
       (with-slots (major-spacing) pane
         (loop
             for child in (sheet-children pane)
             for sr = (xically-content-sr** pane child)
             sum (space-requirement-major sr) into major
             sum (space-requirement-min-major sr) into min-major
  