Changing objects colour is not working...

Well i have lots of objects in the lovely standard grey in my BGE scene, but there is only one way to change the color and thats to set all the color sliders to 0 so it is black. Turning all colors up to full does not result in white, so how does one change the colors of objects? also is there any transparency setting?

Add a material to your object and set its diffuse color. For transparency in the viewport, check the Transparency tab in the object’s material and change the Alpha value there. Then in the Object panel check the Transparency option in the Display tab.

Ahh figured it out now, strange that the RGB sliders dont do anything, except control the brightness, but using the white box to the left of the COL button they seem to work now!