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Click on the drop down list (middle-top of the Preset window), and select mxm files or skies.
In the Preset Browser you can see the mxm material thumbnails...
and the Sky preview thumbnails.
The Presets Browser is very useful if you want to apply your predefined Maxwell files to modo scene elements.
Just drag and drop the preset thumbnails from the Preset Browser onto the modo geometry, Shader Tree, or in case of Sky presets to the render or viewport background. (You can also double-click on Sky presets to import them into the scene.) It is very fast and intuitive.
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