Maria: It looks to me that your light change was done in photoshop rather than poser.  You will have to change some of the colors of your lights.  Specifically all of the green ones to make them more pale.

DP:
It could be done that way, but remember your background image is blurred to provide depth of field.  Plus, too many curves could cause the lights strange angles on your background.  But feel free to experiment and see if it works for you.