the BG system goes a little somethin' like this:
you've got a dialog box in which your character is displayed wearing whatever armor/weapons he's (she's) got, along with a pallet of primary and secondary colors. depending on which color you press in the pallet, parts of your character will be given a certain hue of blue, green, purple, etc, etc. It's all very interactive and on the fly. This might be straight-forward rendering on a scale incalcuable to the human mind, but I doubt it. It's probably some sort of script that adds a "tint" to the colors represented on screen in the appropriate areas. I've seen code that does this sort of thing in less worthy apps, so I assume BG uses something similar. I'm really not sure if you could do this kind of thing in ColdStone, though I seriously doubt it (you could render all those colors individually...).
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Do not follow me for I may not lead. Do not lead for I may not follow. Do not walk beside me, either. Just leave me the hell alone.
-Jedi