Ryand, on the issue of whether the park is open: We stayed there for about four nights over Christmas when we were back in the area and visiting with kids / grandkids in St. Charles. That's going to be an excellent RV park, and is pretty darn good now.
The small staff was extremely helpful and friendly. They've planted about 3000 trees that will take a while to mature, and have plans for a couple of large pavilions. All of the roads are paved, and the sites are packed gravel, although still muddy in some spots. Extensive walking / biking trails wind around the lake, and there's lake access for small boats (under 10 HP, if I remember).
Temperatures got into the teens while we were there, and the wind was about 30 mph coming across the lake and rolling between the levees like a wind tunnel. There's a chain across the entry road at night, and you'll get a key and/or combination for access.
The night we arrived there were only three units there for about 75 spaces. The site we were assigned had a lot of mud, so we moved next door, and stopped by the office to let them know. Naturally, even thought they don't "normally" assign sites, we had picked the only one where they had send out confirmation of a specific site. So with about 70 sites to choose from, we moved about three spaces over the next day, rather than have the other folks reassigned to an identical site when they came. Of course, you already know that the end of the story is that no one ever arrived and occupied that site while we were there.