Go to the root folder of B6 and look to see if you have 2 "Preset" folders, 1 main folder and then another "presets" inside the main "Presets" folder, if so look inside the sub-folder and look inside to see if there's a "Materials" or "Mats" folder, if so, click and drag the materials folder from the sub-folder into the main "Presets" folder. Then open Bryce and try to load or save mats. Or maybe you didn't download or install all the Material Presets files ?

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