Just a couple... minor suggestions... on making the bot mode look even closer to the screen version (which, by the way, you seem to have a knack for doing pretty damn great already) A few spots could use some blue, and a couple could use some red to really up the accuracy.
a quick colour map (using one of your own pics) I photoshopped together

The bands on the feet, on either side of his "I am Optimus Prime" tab, the rest of his vehicle mode's doors, the domes on the outside of his elbows, and two little sections of his shoulder struts are blue on the CG model, and the two hanging pieces of leg armour are red. If you were to add those I daresay it would be the most screen accurate Optimus Prime I've ever seen!
Also, I love your LED works, they really bring the awesome!
- Sam