I am having trouble with the Meadow scene tutorial on Blender guru I got the grass essentials pack, and followed the tutorial, but every time I put the grass in as the tutorial shows, it is a grey color and does not change.  I also cannot change the density, it seems like there is very little grass there that is all grey.  Am I missing some button or something from the tutorial? The link for the tutorial in question is: http://www.blenderguru.com/tutorials/make-grassy-meadow-scene/



Please let me know if I have something wrong here. I have tried going through the tutorial several times and it continues putting the grass part in as grey.  If I just add the grass in to blender by itself, it appears as expected, and multi-green color.
If you look at the very top of the screen for the tutorial in question, you'll see that is made with blender cycles and you are trying to do it in blender internal. Change it here: