When I make this again -- not "if", mind! -- I will shorten the interfacing by about an inch or so from the top, as it makes the gathering a bit stiff, but other than that, the pattern is pretty much ideal. I must point out that I interpreted, "Mark 1" down from the top edge of your bag. Sew a line 1" down from this edge" as that the sewing line is two inches from the top edge, but this is not the case. I suppose that the instructions for 2" down would have been "Sew a line 1" down from this line" -- but be that as it may, you definitely want to sew the cord channel 1" from the top edge.
The bag is actually a little bigger than I'd pictured in my head from the original photos, so that's great! It's definitely small enough to be portable, but big enough for a sock project plus glasses, ruler, pattern (folded), etc. It would also make a great reusable gift bag.
I found this fabric in a drawer recently -- I bought it to make Laura some rompers, so that says how long it's been in the drawer, since she hasn't wanted rompers for sixteen or seventeen years. It is still extraordinarily pretty and cheerful, though! It looked really good with the yard of denim that I'd bought at the same time (sigh ...), but I thought now that denim would be a little too heavy for this bag, and got a short length of blue Kona Cotton instead. I'm afraid I was very unimaginative and just flipped the two fabrics for the other side, but the yellow pleases me so much that I don't mind at all.