You can edit original links that have been converted from the native CAD files. If you do this, then save the changes in an NWF file, then change the link in the original CAD file, and reopen the NWF file in Autodesk Navisworks, then your edit “overrides” will remain. If you haven’t edited the links in Autodesk Navisworks, however, the updated links from the CAD file will appear.
You can reset all links on an object to those that were originally converted from the CAD file. You can also reset all links on all objects in the scene to their original state.
You can delete any links that have been added to your file by Autodesk Navisworks users, and the links that have been converted from original CAD files. You cannot delete automatically generated links, but you can turn them off, so they don’t clutter the Scene View.