AcSmSubset.SetDefDwtLayout
From AutoCAD Sheet Set Manager API

Sets the AcSmAcDbLayoutReference that points to the layout used as a template for new sheets.
Syntax
SetDefDwtLayout(
pLayoutRef As IAcSmAcDbLayoutReference) As Object
| pLayoutRef | Input AcSmAcDbLayoutReference that points to the layout used as a template for new sheets |
| Comments? |