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Save proxy objects: saves ACIS solids and a number of other TurboCAD Pro object with proxies so that TurboCAD Deluxe or Designer can open the file and see representations of objects that are not supported by those applications. Proxies increase the size of the file, but do allow file to open more quickly.
Save Undo: The Undo/Redo performed in the file are also saved when this option is enabled in setup while exporting.