The following VBA example sets the line spacing to a percentage of the character height, verifying that the option was applied.
Sub Test()
Dim d As Document
Dim s As Shape
Dim t As Text
Set d = CreateDocument
Set s = d.ActiveLayer.CreateParagraphText(3, 3, 5, 5, "This is " & _
"sample text to illustrate the line spacing in the " & _
"TextRange object.")
Set t = s.Text
t.Story.SetLineSpacing cdrPercentOfCharacterHeightLineSpacing, 0.3, 0.2, 0.4
If t.Story.LineSpacingType = cdrPercentOfCharacterHeightLineSpacing Then
MsgBox "The line spacing is set to a percentage of the " & _
"character height."
End If
End Sub