AutoPlant SS4 08.11.09.140 x64 bit supports following configuration:
Windows 7 x64, AutoCAD 2012 x64, MS Office 2010 x64 or MS Office 2007 x32
AutoCAD 2013 is not supported.
As well comparing file size it seems that executable on your side is not complete, please try to re-download it.
I hope this information will help.
Regards,
Artiom