You will have better results using automation to access these objects directly. See the 'Library Manager and Library Editors Automation Reference' in the help. There it describes how you can get references to the part editor, cell editor, and padstack editor. You may have to use more than one of them, as for example there will only be a reference to a padstack in a cell object, so you then have to go to the padstack editor and get that padstack to get more detailed infomation about it.
There are some examples here on the Communities website on how to access all the objects in the part editor. The others are similar.