Why aren't certain modules or learning objects showing up in Course Preview or Published packages?

Learning Objects:

• The LO is empty (contains no pages).
• The LO contains Test Questions only.
  
  Note: If you want to use these questions you'll need to add or move the questions into an LO with content pages or add a content page to the LO containing your test questions.
  
  
• The LO is set to "Do not publish learning object" in the Learning Object Properties.
  
  Note: The "Do not publish learning object" option is helpful if you'd like to make part a course available, but still want continue to add new content to make available at a later date.

Modules:

• The module is empty.
• The module contains only LOs with the above mentioned specifications.