Как програмно из C# создать слой дла Autocad?

Imports System
Imports Autodesk.AutoCAD.EditorInput
Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.Geometry
Imports Autodesk.AutoCAD.Colors
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.ApplicationServices
Imports acadApp = Autodesk.AutoCAD.ApplicationServices
Imports acadDB = Autodesk.AutoCAD.DatabaseServices
Imports acadED = Autodesk.AutoCAD.EditorInput
Imports acadGo = Autodesk.AutoCAD.Geometry
Imports acadRT = Autodesk.AutoCAD.Runtime
Imports acadCol = Autodesk.AutoCAD.Colors
Public Class Class1
    <CommandMethod("ALB")> _
      Public Sub Doit()
        Try
            Dim oid As ObjectId = _
            MakeLayer("NewTableLayer", "Continuous", 34, True)
        Catch ex As acadRT.Exception
            MessageBox.Show(ex.StackTrace)
        Finally
        End Try
    End Sub
'//
'//
'//
    Public Shared Function MakeLayer(ByVal layerName As String, ByVal ltypeName As String, ByVal layerCol As Short, ByVal toPlot As Boolean) As ObjectId
        Dim db As Database = HostApplicationServices.WorkingDatabase
        Dim doc As Document = acadApp.Application.DocumentManager.MdiActiveDocument
        Dim dloc As DocumentLock = doc.LockDocument()
        Dim ed As Editor = doc.Editor
        Using tr As Transaction = db.TransactionManager.StartTransaction
            Dim lrt As LayerTable
            Dim layr As New LayerTableRecord
            lrt = CType(tr.GetObject(db.LayerTableId, OpenMode.ForWrite), LayerTable)
            '//
            If lrt.Has(layerName) Then
                db.Clayer = lrt(layerName)
            Else
                '//
                layr.Name = layerName
                layr.Color = acadCol.Color.FromColorIndex(ColorMethod.ByAci, layerCol)
                '//
                Dim ltypeID As ObjectId
                Dim ltt As LinetypeTable
                ltt = CType(tr.GetObject(db.LinetypeTableId, OpenMode.ForWrite), LinetypeTable)
                If ltt.Has(ltypeName) Then
                    ltypeID = ltt(ltypeName)
                Else
                    Dim ltype As New LinetypeTableRecord
                    ltype.Name = ltypeName
                    ltt.Add(ltype)
                    tr.AddNewlyCreatedDBObject(ltype, True)
                    ltypeID = ltype.ObjectId
                End If
                layr.LinetypeObjectId = ltypeID
                layr.IsPlottable = toPlot
                lrt.Add(layr)
                tr.AddNewlyCreatedDBObject(layr, True)
                db.Clayer = layr.ObjectId
            End If
            ed.Regen()
            tr.Commit()
            Return lrt(layerName)
        End Using
        dloc.Dispose()
    End Function
End Class