You can access material properties via the Material page of an object's Properties window Renders: Select which render engine you wish to select a material from: RedSDK, Lightworks, or both. Category: Groups of materials such as glass, metals, stone, and wood, or the name of an open drawing.
Material: This field depends on the category. For example, if the Category is Metals, the materials include brass, iron, aluminum, etc. Material: The list of the materials available in the selected category. Available In: Shows which of the render engines have definitions for the selected material. Edit... Opens the Render Manager.