Code:
Option ExplicitPrivate Sub AddNamedGeometry()
Const iLogicAddinGuid As String = "{3BDD8D79-2179-4B11-8A5A-257B1C0263AC}"
Dim oPartDoc As PartDocument
Set oPartDoc = ThisApplication.ActiveDocument
Dim oCompDef As PartComponentDefinition
Set oCompDef = oPartDoc.ComponentDefinition
Dim oFeats As PartFeatures
Set oFeats = oCompDef.Features
Dim oiFeats As iFeatures
Set oiFeats = oFeats.iFeatures
Dim oiFeat As iFeature
Set oiFeat = oiFeats.Item(oiFeats.Count)
Dim oFace As Face
Set oFace = oiFeat.Faces.Item(1)
Dim oAddin As ApplicationAddIn
Set oAddin = ThisApplication.ApplicationAddIns.ItemById(iLogicAddinGuid)
Dim iLogicAuto As Object
Set iLogicAuto = oAddin.Automation
Dim oNamedEntities As Object
Set oNamedEntities = iLogicAuto.GetNamedEntities(oPartDoc)
Call oNamedEntities.SetName(oFace, oiFeat.Name & "_Face")
End Sub