A good practice that I used in InstallShield scripts professionally was to disallow installing on the desktop itself or other problematic locations in the first place. (It's safe to use a desktop subfolder and safe to run the installer from the desktop if it installs the files elsewhere.) The free open source Inno setup program has the same functionality. You can indeed force installation to C:\LuaRT if you like, but it is better to allow user choice of location as long as problematic choices are not allowed. I admit that many alleged professionally-built installers will gleeful let you install to dangerous locations so the uninstaller could delete system32 if you mistakenly installed there, far more problematic than deleting your desktop. This is however a gross violation of best practices. Software companies are unfortunately this slipshod with installers every day. I know--in my work, I've had to argue with my own managers to follow best practices.
