Got a little bit done on the maternity corset -- namely I got one side put together and some boning inserted to see how it would lay. I'm pretty pleased with it so far. The bust openings are similar to a nursing corset I saw from 1870s, and I'll be attaching a flap there which will hook closed at the center front.
Shown below is the corset without the belly. This dress form is skinnier than I am usually, so I have to take into account that the corset will look rather "straight-up-and-down" on the form rather than on my real body. Trying it on my body will be the real test. :)
Next up: sewing up the other side and adding buttons/buttonholes along the front.