I finally gave in to regular upgrade request pop-ups on my Kubuntu 10.10 installation. The upgrade was quite fast (a little more than 1 hour). It gave me a warning that something went wrong (exit code 1) and I noticed at least two most annoying problems:
all my attempts to add an additional keyboard layout had no effect at all. (I had done that in previous versions with no problem at all.)
When I click an icon of an application on the panel it will no longer start the application but give instead the whole menu to choose one from.
Is there a way to to at least investigate these problems without reinstalling from scratch?