Whilst searching for reference pictures to paint my Knockout toy I came across Jennifer Hoffman's website, Portfolio: Jennifer Hoffman - Transformers Prime Rigging I found it interesting to see these images and also note that these images were not created for the show itself but for promotional material hinting that those that create promotional material of the characters do not necessarily work on the show itself. I recognise at least one of the images there as that used on the box art. For more information check the website, the slideshow shows most of the characters listed
Here's the thread http://www.tfw2005.com/boards/trans...rmarked-renders-knock-out-breakdown-more.html , though it was posted ages ago so you could have easily missed it.