LDD lacks almost all functionality
As Phil B commented - you'd probably be better off with Studio now. This was originally developed by a team at BrickLink, and when they were acquired by The LEGO Group made the following statement:


  
  What about Studio and LEGO Digital Designer (LDD) – what will happen with the two digital building experiences since they’re quite similar?
  The LEGO Group is planning to support and evolve Studio and will review opportunities for both services following the closing of the deal.  
  


So going forwards, Studio is the supported option. If you feel you really must stick with LDD, please also ensure that you use the last-but-one version, as the very latest version is missing a number of elements.

Finally, ensure that you download the installer from official sources (such as the LEGO CDN as linked in that answer), rather than "free software" sites, which might have tampered with the package.