If you use standard Bayesian sorting, depending on the amount of votes, you will have images with no stars appearing in front of images with one star. Obviously, whilst this is the behavior we want, from the users viewpoint it doesn't make much sense.
In order to rectify this situation, it's a very simple fix (although it took me quite a while to work through all your functions... :P )
In bwbps-layout.php, add this on line 421:
if($image['bwbps_br_rating']) $rating['avg_rating'] = $image['bwbps_br_rating'];
And that's it!
From a UI point of view, you will need to make it clear that you're displaying the AVERAGE rating, not the user rating. But anyways, hope this helps :)
- WindupHarlequin