In September they closed for a few hours between lunch and dinner...I cannot remember the exact time though.
We caught the boat to FT. Wilderness from MK near where the ferry docks.
We had a nice lunch - sandwich bar, soup and salad bar, a couple hot dishes, apple crisp for dessert. There were no crowds at all, but as I mentioned above, the restaurant closed while we were there (we were allowed to finish and they kept the buffet set up, but new people were not allowed in).