Can we score different color cubes on the tower stacks? How does that scoring work?

In both the Teamwork Challenge and the Robot Skills Challenge, Highrises must consist of Cubes of the same color. In the Programming Skills Challenge you are allowed to have Highrises with Cubes of different colours. However in the Programming Skills Challenge if you build a Highrise of Cubes of all the same color, your Highrise will earn you double the amount of points.