Changing the color of window light and billboards

[Khyrpa]

I created this short video to show if I got what you meant:
http://www.youtube.com/user/superkhyrpa?...isWXIgi0Ek

Just place a billboard in front of the window and use it to adjust the color of the window.
And to change the color of billboards, just connect a billboard into any light and change the color of the light with FadeLightTo function (in this video its just the lights own flicker settings changing the color).