I’m enjoying Anna’s story. Attached is the chapter with my comments–hope you find something useful.
As to commas, I studied CMS for my certificate in editing from UC Berkeley Extension and I still have to look things up sometimes. 🙂 My understanding is that editors don’t expect you (or any writer) to be an expert. The main thing I see (in terms of commas) is that many people don’t use the serial comma, which CMS recommends. Anyway, I haven’t noticed much amiss in your comma usage, but I’ll try to be more aware from here on out.