To avoid the boxes being greyed out ensure you have on one of the pre-defined views obtained with the little 'house' icons at the top of the page. You would use the top view for a plan view for example. Secondly on the menu along the top ensure you click 'camera'then 'parallel projection'. You can't print to scale in perspective. It should work for you now.
You can read about the material editor here (SU Guide > Modele settings and managers > Material browser).
Transparency is somewhere around 2/3 down on the page (not too much info though when you learn how to use it you'll see that not too much info needed...) π