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If you already have a Solaris Material Library node you wish to load a preset material into, simply select the materiallibrary node and select Import into Selected Material Library.
This will import the selected material preset into the selected Material Library.
If a materiallibrary node is not selected or does not exist, you can choose Import or Import and Assign to Selected and that preset will be loaded into a newly created Material Library
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Saving Materials
Currently, there is a limitation in Solaris that will only export one material from a selected materiallibrary.
Simply, select the materiallibrary node and click on the new material icon in the Preset Browser