I've got the waistcoat finished and the oil washed out of the yarn - it was a coned industrial yarn. The cashmere is gloriously soft. I am wearing it under my cardigan as I type and it is lovely and warm.
You can see here how leaving the wraps of the wrapped stitches from the short rows on the back - not knitting them together with the wrapped stitch - makes a little feature line up the armhole.
And this is the back. The instructions were to knit the edging and then sew it in place, but instead I knitted it onto the stitches of the back - which I had left live instead of casting off. As I was a little concerned it might be a bit wide across the back of the neck, I knit 3 together instead of two together when joining at a few places across the back.