With such unclear instruction in bits and pieces I am even more reluctant to mess with the registry especially where terms and confusing. "Add" to what? . Add where? What "images" are you talking about? You have not defined your terms and, unless yo do, communication is impossible and no one can know what you are talking about.
"On the File menu, click Import and import the .reg file on your desktop."
None more example. No! there is no ".reg" file on the desktop. That file downloads as a 'ini file. So once again you are not communicating clearly and consistently and that is in invitation do disaster.
All this is the reason is why others in this conversation do not want to mess with their registry.