request for enhancement: note missing items for control panel

[Anthony Ewell]

Dear XFce Developers:

To my astonishment, CentOS 4.4 does not include
switchdesk-gui (switchdesk-gui.py) with its
"workstation" install (the "all" installation does
get it).

XFce 4.2 will show switch desk gui in its control panels of
configuration tools only if it can find it.

Please consider showing a blank icon with some kind
of message when the control panel can not find an
item.  This would tip the user off that something
is missing and would reduce a lot of frustration.

Many thanks,
--Tony