I actually finished this and felted it a couple of weeks ago. Sewing it together was really not that hard, but the 48" of seed stitch over 11 stitches for the strap took some patience (and really made me rethink using seed or moss stitch for the dreaded Berroco Comfort blanket).
Anyway.
Before Felting
And After Felting
I added a magnetic clasp to the inside of the flap to help hold the thing down. I'm really quite pleased with how it turned out, despite the wacky weird pattern I mentioned previously. It didn't even take very long for it to felt (20 minutes) or to dry (a day).
So that's all right, then.