If I understand correctly: 1) put the .mat file anywhere - load Bryce and open the Material Presets and click on "Leaves". Hit import and navigate to the .mat file and hit the OK checkmark. 2) Create a tree and open the Tree editor. Now hit the Material Edit button (bottom right), 3) Now hit the right facing triangle a the top of the preview window and load the preset imported in 2). Exit the tree editor and render. HTH; Dan