2 registry entries are not really that much,the other step is saving you presets.
more than half of those steps are just basic steps like "open Command prompt"
or "hold down windows key plus + R", exc.
almost every program leaves behind traces in the registry.
I wouldn't blame the installer.
I do agree with you about uninstall software though, I use it for everything, I use ur uninstaller.
though ive heard good things about revo.