I'm sorry, only the memory warning was a duplicate of bug #116870
However, the non-english part of this bug description can be fixed in gconf-editor:
1) Go to apps/compiz/plugins/decoration/allscreens/options/
2) Right click shadow_radius and choose "Unset Key"
Now, you'll only get the memory warning, but gnome-compiz-preferences still will not be shown. Strangely, if you load two simultaneous instances of gnome-compiz-preferences, both will be shown.
I'm sorry, only the memory warning was a duplicate of bug #116870
However, the non-english part of this bug description can be fixed in gconf-editor:
1) Go to apps/compiz/ plugins/ decoration/ allscreens/ options/
2) Right click shadow_radius and choose "Unset Key"
Now, you'll only get the memory warning, but gnome-compiz- preferences still will not be shown. Strangely, if you load two simultaneous instances of gnome-compiz- preferences, both will be shown.