I'd like to pass along my "Oops" corrections, in case you'd like to make this bag!
After step 4, it should have told you the following:
a) Layer outer bag over wrong side of lining (21” x 42”) and baste to hold together for quilting.
b) Stitch in the ditch along all piecing to stabilize piece. Optional: Quilt a Large Meander on all red sections. Trim.
Then the divider panel with pockets will be sewn to the back section (see step 16) – here is a clarification for that:
c) Baste Inner Computer Panel to inside back section of bag, 1 ½” from seam as shown. Top edge of Inner panel should face flap.
Visit www.quiltmag.com to request a copy of the magazine, if you can't find a copy where you live.
Have a great day! -Kris