Can't create Railing. Thickness of Rail or Balusters might be too small. If you don't want Balusters, specify "None" for Baluster Shape. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
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