I had recently uploaded an example and *.Capx file of an editable "Loading Layout". Once of the things I had included was an example of how to smoothly change the colour/appearance of a sprite. More on the "Loading Layout" example can be found here. Click Here!
I thought it would be worth creating an individual example aimed primarily at displaying a sprite in a variety of shades and appearances. So I've created and uploaded Sprite Colour Changer to the Scirra Arcade. This can be found here. Click Here!.
The *.Capx file can be downloaded directly from:English Acorn: C2
-Adam
**Update 06/12/2013:
-Removed redundant and broken links.