Go here and find your color(s) that you'd like to loot:
http://ac.wikkii.net/wiki/User:Sanddh/Guides/Armor_Color_Table
You'll want the Hex(RGB) code for the color(s), then in the VT loot editor, add a new rule to keep, under the pull down find one similar color and enter your Hex(RGB) code where it applies. You can also put in the max difference in hue that would be acceptable for you instead of entering multiple colors.
So for example, if you want bright greens in old style armor colors like new leaf and spring green you could put in 5AAF0F and/or 60BE11
Typically, I think the hue difference of 10 is too much, find a color you like and lower it down to like 0-3 if you want a close match.
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Cereal and Milk.... cause my other vnboard name got taken!