[ajenner]

Yes, I'm reenigne from the demo. Feel free to contact me at [e-mail].

I'm not sure what you're doing with the colour mixing on that page but I'm wondering if you're just applying a gamma curve to the mixed result. This is what I meant:

sRGB interpolation:

  r_final = r_1*x + r_2*(1-x)
  g_final = g_1*x + g_2*(1-x)
  b_final = b_1*x + b_2*(1-x)

linear RGB interpolation:

  r_final = 255*((((r_1/255)^2.2)*x + ((r_2/255)^2.2)*(1-x))^(1/2.2))
  g_final = 255*((((g_1/255)^2.2)*x + ((g_2/255)^2.2)*(1-x))^(1/2.2))
  b_final = 255*((((b_1/255)^2.2)*x + ((b_2/255)^2.2)*(1-x))^(1/2.2))

The real gamma correction formula is actually slightly more complicated than that because it's linear up until the sRGB value is about 10 then then follows a ^2.4 curve but the difference is too small to notice.