The "meatloaf" is a pound of lean ground beef with a teaspoon of calcium carbonate and a tablespoon of dry reptile vitamins. You can mix in certain fruits, vegetables, or dead bugs if you want. Freeze it in little balls and take out a ball as needed. I did something similar with my hedgehogs but found the balls start to look off in a few weeks or so after making it. It would only be useful if your turtle eats raw ground beef.
You want Gracie to get into the dig box but also back out and also have room to dig. Ramps may or may not work depending on her personality. I think you'll have to experiment. You might start with a small cat litter pan. To make a ramp for my sailfin lizard to get in and out of her pool, I bought wire "under-the-sink" storage shelves and bent the legs so it stays at an angle making a ramp. Smaller turtles might get their feet stuck in the rungs so they can be covered with something or something else solid used.
I've never had an ornate box turtle or kept Eastern box turtles except for very short term (wild ones being treated) so you should consult the links on my box turtle page for expert advise. There's a Yahoo box turtle group that I recommend. They should answer your questions. The web site is
http://pets.groups.yahoo.com/group/boxturtlelist/Good luck!