Nice, looking good so far. I like your idea on the 2 part molding if you will. Although I don't know of anyone every doing it that way. Any concerns with how well the interface boundary binds or interacts?
Looking forward to seeing the top half, or the slant bed surface plate/mold portion of your model. I'm guessing you'll imbed your spindle mount hardware as well any linear rail (guessing) reference ledge or mounts as well.
You might want to make 2, so that you can practice or prototype out on the first and master on the second, Then I can haul the prototype one off to scrap for you .