look at this, at nr 1 I am at desktop 2 and at nr 2 I am at desktop 1, thats the only change i do. (Im not really sure when this occured yesterday or today, the terminal was very wierd when using transparent but after i rebooted it seems to work...)
http://hem.passagen.se/firedance1989/wtf1.jpg
http://hem.passagen.se/firedance1989/wtf2.jpg

Have you opened Nautilus at all? Nautilus has the responsibility of drawing the desktop wallpaper and icons under Gnome, but also does this if it is launched under any other desktop environment.

What has probably happened is that you opened Nautilus in KDE, closed the filemanager portion, but the Nautilus process stayed running. When you log out of KDE, it saves what windows you have open, including the Nautilus "window", and will reload Nautilus on that desktop every time you log on.

The solution to this is to kill the Nautilus process with killall nautilus or from KDE SystemGuard *then* logout.

Why they gave the responsibility of drawing the desktop to a file manager, I'll never understand...