I have never stolen Software before or used Torrents.
Did they supply a "crack" version? If so, then you would have to open the Rosetta Stone program folder and "copy and paste" the "crack" into the folder that the "original" file is in, to replace the original with the crack. This would take place after the program is installed.
I am just guessing and I may be mistaken. But I am pretty sure that is how it is done.