Technically those buttons are what Philips considered "color". The TSU6000 has a very limited color palette that tended to work best with grey and blue. You can easily replace existing buttons with new images, as long as you've added them to the gallery or have another panel with those images.

It might pay to read through my review [Link: remotecentral.com] and the Pronto FAQ (linked at the bottom of this forum page).