For reasons only interesting to me, I tried raw sienna rather than yellow ochre for this one.
This is mostly casein with just the addition of lemon yellow gouache paint I have in stock.
I created a blow-by-blow account of the painting process of this one:
I returned to gouache for this one and found I like the paint properties much better than casein. I seem to be able to manage the issue of reactivation if I let each layer dry thoroughly and save white mixtures for the very last.