did u email me about this? If that is the case I have replied you.
There are 2 options to do this.
1) Use a php widget and put in the code to display the top rated post (it is in the readme.html)
2) Download my wp-stats (WP-Stats 2.10) and activate it and its widget component. Then go to WP-Admin -> Options -> Stats, and check the box that says top rated post.