public Paragraph InsertShape( 
   Shape s,
   int index
)

// Create a document.
using (var document = DocX.Create("Test.docx"))
{
  // Create a shape and add it to the document.
  var shape = document.AddShape( 50, 50 );
  shape.OutlineColor = Color.Green;

  // Create a paragraph and insert the shape at its 16th character.
  var p = document.InsertParagraph( "Here is a simple default rectangle positioned on the 16th character of this paragraph." );
  p.InsertShape( shape, 16 );
  p.SpacingAfter( 30 );

  // Save all changes made to this document.
  document.Save();
}