Re: get FamilySymbol from Family

For fabrication you need to use BuiltInParameter.ELEM_FAMILY_PARAM to get the name.

here is a quick macro Example.

Document doc =	this.ActiveUIDocument.Document;
View view = doc.ActiveView;
 FilteredElementCollector collection =  new FilteredElementCollector( doc,view.Id ).OfClass( ( typeof( FabricationPart ) ) );
TaskDialog.Show("Fabrication Part", collection.FirstOrDefault().get_Parameter(BuiltInParameter.ELEM_FAMILY_PARAM).AsValueString());

hope it helps :)