not bad, but you need to find someone to replace the teeth with good ones. speaking of which, if you find someone who actually can do that, let me know. i need a set of cool teeth to be put on Crusher
as for the skin, here's my opinion on what it needs done to it:
1- dont make the orange bit so bright, or atleast, not so bright that it wipes out the skin's wrinkles underneath. i made that mistake in Photoshop on Crusher, but quickly corrected it when i thought of how it would look.
2- make the lower half of his body [the pale bit where his neck, stomach and lower part of his tail are] a lighter, near turqoise colour. a colour closer to turqoise on the back would also mimic the Warpath Rex more accurately.
3- after making the orange colour slightly darker and fainter, give it a white outline, using the recolour option with a fine brush. or use the normal brush, but keep your painting halfway out of the area you plan to paint.
4- as mentioned before, the teeth need fixing [dont forget to tell me if you find someone who can make custom teeth!!!

]
with those 4 things, i think this rex has quite a future as a popular mod download.