Small script for Logitech keyboards with different backlight colors. Changes the color of the backlight permanently, smooth! Shouldnt be hard to make it use on keyboards with just two colors.

lg_color_switcher.lua

function OnEvent(event, arg)
    if (event == "PROFILE_ACTIVATED") then
        color()
    end
end

function color()
    r1 = 0
    g1 = 0
    b1 = 0
    while true do
        r2 = math.random(255)
        g2 = math.random(255)
        b2 = math.random(255)
        for loop = 0, 255, 5 do
            SetBacklightColor((r2*loop+r1*(255-loop))/255, (g2*loop+g1*(255-loop))/255, (b2*loop+b1*(255-loop))/255, "kb");
            Sleep(50);
        end
        r1 = r2
        g1 = g2
        b1 = b2
    end
end