You can register or unregister a customized Scheme file through your Fluent setup using the context menu for the Fluent Setup cell. Fluent loads this registered scheme file at startup. To register a scheme file, use the Register Startup Scheme File... command from the context menu for the Fluent Setup cell. Likewise, to unregister a scheme file, use the Unregister Startup Scheme File... command. If Fluent is already started, these menu commands are disabled and grayed out.