The location of the installed Maxwell Render environment application can be set in a dialog which is located under Edit - > Preferences - > Maxwell Render Settings… in the menu.
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The dialog expects the location of the Maxwell and Mxed executables. When the path changes the plug-in verifies if the given file exists and displays an error message if not.
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If the MAXWELL2_ROOT environment variable is set then the plug-in will use it by default and no manual settings are needed.
The settings are stored in the maxwell.pref file located in the HOME/houdini[version] folder.