Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
I believe there should be a clearer outline of a back button as down below it says escape for back but pressing esc takes you back to the main menu. However clicking on this will send you back to the previous customization screen.