If a window is currently active, its button is displayed as if it were pressed down.
You can also click on the window buttons. Depending on whether the window is currently active and/or minimized, this will activate or minimize the application which the button represents. Minimizing works only for frame windows which have a minimize button though.
The window list widget accepts colors and fonts that are dropped on it.
You can configure the window list widget to suppress the display of
certain windows ("filtering").
Right-click inside the widget and select "Properties". A
dialog will pop up which allows you to filter out any windows that you don't
want to see.