I installed and tested it on my live blog prior to posting the link here and it worked for me.
Open report-post.php and go to line 253. Uncomment this line -->
so that it reads -->
The "Report Post" link will now appear at the end of your posts.
There was another plugin I tested some time ago that worked even better than the above but unfortunately it is no longer being maintained.
The download link renders a 404 and I don't see any contact info for the author on the site.
As a side note, Dagon Design has a report comments plugin. If you ask them nicely perhaps they may get around to modifying it.