Can you please attach your ~/.xsession-errors file to see if there is anything specific outputted by the panel or window-picker-applet before it closes.
Also, does the applet not start at all, or crashes during use?
Can you please attach your ~/.xsession-errors file to see if there is anything specific outputted by the panel or window- picker- applet before it closes.
Also, does the applet not start at all, or crashes during use?