Version: (using Devel) OS: Linux Installed from: Compiled sources Its seems that the plasma widget in the top right corner is rendered behind google and superkaramba widgets. If you place a google or superkaramba widget close to the widget in the top right corner it will become impossible to use the top right corner widget for locking/unlocking because it will be rendered behind the superkaramba/google widget. The screenshot below will probably give you a better idea about what i am talking about. http://www.nperfection.com/other/kde4daily-2.png Native plasma applets do see to work fine. This bug was tested on kde4daily with the latest patches and updates.
that's because you are using superkaramba and google gadgets as separate applications, so they are windows. using their integrated into plasma mode they will work as expected