Maybe if you just make it all white, you can just have multiple scripts for different colored ones.
If you insert this little bit somewhere:
doColorShift = true;
colorShiftColor = "0.25 0.25 0.25 1.000"; Then just change the color you want it to be. It's RGB, so the first value is red, second green, third is blue, and the fourth is alpha, or transparency.
I'm not certain it will work, because I hardly script at all, but you could try.