Before the patch, the Examples menu was disabled while a demo was running by setting the Menubutton state to DISABLED versus NORMAL. This does not work for the cascaded Menu.  The result was buggy behavior when loading a new demo while the previous one was running.

Since having the menu disabled was annoying anyway, I changed the loading code to do what the Stop button does. I also cleaned up the control flow of a couple of related functions and the return value for the Nim demo.

The next patch will removed the now unused menu state setting.