Systems Settings Need to be Run as Root
Short Answer: In /usr/lib/kde4/bin/ run sudo ./systemsettings or run as root. In terminal of course (Applications=>Accessories=>Terminal).
2 Hour Long Answer/ Linux CLI Lesson:
I had been wondering about this myself, but usually the reason for this in KDE is because one is not in administrator mode. The odd thing is there is no administrator mode option in the GUI, so one needs to log in as root (administrator) via the command line and run the binary (executable) using its name as a command. I found the command by creating an icon for System Settings on the desktop by right-clicking the entry and selecting add to Desktop. If you right click the System Settings icon/widget on the desktop and select "Icon Settings" and go to the Application tab, in the third entry one can see the command to run the program. This also happens to reveal the location of the binary. It is in /usr/lib/kde4/bin/, or a folder for binaries associated with KDE4 (bin is usually a shorthand for binary). The binary is systemsettings, so if we want to run System Settings, we need to run the systemsettings binary because this is the binary that runs the applications. If you have the same setup as me, you should see some options after /usr/lib/kde4/bin/systemsettings. I am honest when I say that I do not know what these are. But I have found that it is easy enough to run the binary with superuser privileges by entering "cd /usr/lib/kde4/bin/" (cd=change directory) and entering "sudo ./systemsettings". Sudo, in case you did not know, stands for superuser (root/administrator) do, i.e. run the command with superuser or root privileges, even thought the user is not superuser. If you want to login as root, enter "sudo passwd root", to create a password for root or superuser. You should see "new UNIX password:" type in your password for root as prompted. Now you can also run commands actually as root by entering su (superuser) and entering root's password, instead of having to enter sudo every time to get superuser privileges repeatedly. You'll notice that the console should say root@(xxx)$ instead of (username)@(xxx) if you are root. The ./ means in this folder, because . stands for your current location, in this case /usr/lib/kde4/bin/, but to shorten the typing we just type "./" period. Two dots or ".." indicates the next directory up in the hierarchial structure in this case /usr/lib/kde4/, but we have no use for that at the moment. Just telling you because cd .. is a useful way to move around directories. Anyways ./systemsettings means run the binary sytemsettings in the current location. This needs to be done because the terminal usually looks for commands in the PATH. PATH is a variable which is the location where the system looks for commands or binaries to run when a command is entered into the terminal. ./ tells the system to look in the current location not the PATH, for the binary systemsettings. You can see the location of PATH by entering the command "echo $PATH", I'm not sure you can use that without root privileges.