How can I open a new ChemDraw file in an older version of ChemDraw?
You need to save your new document in the appropriate older ChemDraw file format. Open your ChemDraw document in the version of ChemDraw it was created in. Choose Save As from the File menu and choose the appropriate older ChemDraw format from the File Types popup list. For example, choose ChemDraw 3.x or 2.x. Please note that features present in documents created with a new version of ChemDraw will be lost when you save in an older ChemDraw file formart that does not support the features.