There is a very, very minute difference between your measurements and mine with a map that I just tested with. Mine has differing dimensions from yours, as well. Combined with the fact that the variation here is so small, I'd say this example falls under the umbrella of what I meant when I said "With as much room for variation as the MCT allows for, I strongly doubt there's one universal set of settings for all possible maps." I'm glad these settings work for you though!
Also, re: "Scene Dimensions: 2310 x 1426 (the image itself is 2280 x 1408; don't know why this differs)," I would wager this is because when you set up the scene in Foundry, you used an image with 2310 x 1426 dimensions, *then* replaced the background image with your new map image. Foundry doesn't automatically update dimensions for scenes when you switch the background image (after the first time).
And you were right! Your original settings worked just fine once we started with a fresh scene. Thanks again.
