I did a custom install...chose KDE & Gnome support. Machine
defaults to gnome as usual. This is OK. Open up an xterm &
type "switchdesk"...errors with exec: switchdesk-gnome: not
when you did the custom install, you missed the switchdesk-gnome
package. I have fixed switchdesk to not report an error for the next
release, but the real fix for now is to install that package. Then
your problem will go away.