You do it the same as you would for Poser.  Like hborre, I did a search at Rendo's story, there are no "Sofia" products, there is a "Sophia" character by adamthwaites.  If it is "Sophia" you have it for V4 and Genesis and both Poser and Studio.  Let me be blunt, the ReadMe file gives very clear instruction on how to install the product, as long as you know how to use a computer.  This seems to be your problem, you just don't know enough about computers to be messing with programs of this complexity.  I am now going to make the most extreme and controversial suggestion ever, one that may even get me banned.  I want you to use the 'Help' function in the Start window.  Then type in "System Restore" in the search area.  Carefully read everything that comes up.  Once you think you understand how to do a restore I want you to restore your computer to its earliest point possible.  Now shut off the computer, get to a bookstore or your local library.  Ask for the best books they have to teach a newbie about computers, both general knowledge and OS (Operating System) specific.  Better still would be to find and take a course, there are probably many free or low cost ones available in your area.