You are going to get some kind of troubles if you messed with your preinstalled packages like, for example, in this thread. I would expect a man of your calibre to know how to deal with it
BTW, isn't apt-get upgrade supposed to be discouraged? I must say I've never used in myself on my N900.
Fully agree with all of the above. You are right, community-ssu-enabler is the icon and should go away after a successful installation (the package remains though). The libcpaboutcssu package is what displays the CSSU version info in Settings. I don't have them either and can live quite happily without them.
Install status-area-orientationlock-applet. This will add an entry to your system menu. Use it to lock your phone in landscape. Uninstall status-area-orientationlock-applet. Job done.