This is quite harmless. It is a message we built into the software that appears
when you click the left mouse botton on an inactive part of the setup
home screen, like between two buttons. Nothing else happens.
It was needed in testing the new Vista software on Windows, to see if
Vista “knows” the mouse is there. Please disregard this message, you should
only see it if you click on a “dead” area of the setup control panel.