After uttering many, many curse words, ripping a few seams, and acknowledging my defeat at the hands of what looked like a straightforward pattern, Kiddo has a new messenger bag.
Unfortunately, I failed to read the instructions properly and ended up boxing the corners three inches from the edge instead of three inches across. The resulting bag is much boxier than it should be but at least it is consistent. However, it may not fit her agenda which was the goal. OOps.
The other big fail? Poor choice of fabrics. The main fabric is heavy and slippery and frays easily; the poly-cotton tshirt was too stretchy; and the cotton I used to line it all was thin and slid away from the main fabric. Grr.
Aside from the unintentional cornering modification, I made one other change to the strap. Due to the various qualities of the main fabric, sewing a quarter-inch seam along a four inch wide piece of that stuff was very tricky -- tricky enough that I eventually gave up, cut a piece 8 inches wide and folded the edges into the middle then folded it in half. The finished strap was a full two inches wide.
In the end, I am happy to have finished the bag but content that I will not be attempting anything similar any time soon. Happily, it is functional which means it is not going to be sent to Craft Fail either. Besides, Kiddo seems to like it.