Very strange, since those are the commands sum use to install/change usplash theme.
That it should fail to change other settings is even more weird.
Try launching it from a terminal with sudo startupmanager (yes, use sudo not gksu since it may block some output).
Then try changing some settings that does not work and paste the terminal output here.
Very strange, since those are the commands sum use to install/change usplash theme.
That it should fail to change other settings is even more weird.
Try launching it from a terminal with sudo startupmanager (yes, use sudo not gksu since it may block some output).
Then try changing some settings that does not work and paste the terminal output here.