I was able to finish the opaque version in gouache. I have to say that I'm really liking gouache. My only complaint was that I had to go over the white a second time because the layer turned pink, which I'm assuming happened because I reactivated the paint underneath. I really enjoyed doing the moon this way and mixing my own version of payne's gray.
I haven't been able to finish the opaque version yet, but here is my final project in watercolors. I hope to do the opaque version sometime later this week. I really enjoyed this class and learned so much. I have both gouache and acrylic gouache and am still trying to figure out how I want to use them but blending was such a mystery to me still. Thanks for all of the info!