I think an important piece of data is missing here...
I'm currently typing this on a Mac. When you red X something, it stays in the dock, and if you click on it, it opens back up unless you right click and quit it. The Stadium app, however, does not open back up when you click on it in the dock. You have to right click on it, quit, and then completely restart it from Finder, unless you've got it living on your dock. The issue is, once you red X it, you can't re-open it without quitting it on the dock, which is unlike any other app.