The option SelectedLayout of the Translator Addin of DWG can specify the layers to import to the sketch.
oOptions.Add "SelectedLayers", "Layer1"
you can also specify several layers, e.g.
oOptions.Add "SelectedLayers", "Layer1,Layer2"
Sub ImportDWGIntoSketch()
'DWG translator
Dim oDwg As TranslatorAddIn
Set oDwg = ThisApplication.ApplicationAddIns.ItemById("{C24E3AC2-122E-11D5-8E91-0010B541CD80}")
Dim oData As DataMedium
Dim oContext As TranslationContext
Dim oOptions As NameValueMap
Set oData = ThisApplication.TransientObjects.CreateDataMedium
Set oContext = ThisApplication.TransientObjects.CreateTranslationContext
Set oOptions = ThisApplication.TransientObjects.CreateNameValueMap
' Specify a DWG file to import it into sketch, please change the path name as needed
oData.FileName = "C:\Temp\mytest.dwg"
Dim oDoc As PartDocument
Set oDoc = ThisApplication.Documents.Add(kPartDocumentObject)
'add a new sketch
Dim oSk As PlanarSketch
Set oSk = oDoc.ComponentDefinition.Sketches.Add(oDoc.ComponentDefinition.WorkPlanes(3))
oSk.Edit
oContext.Type = kFileBrowseIOMechanism
oContext.OpenIntoExisting = oSk
' Specify the layers to import
oOptions.Add "SelectedLayers", "Layer1"
‘oOptions.Add "SelectedLayers", "0,Layer2"
oOptions.Add "InvertLayersSelection", False ' Set if import the selected layers in above setting
' Set the ConstrainEndPoints
oOptions.Add "ConstrainEndPoints", True
' Specify the units of DWG file
oOptions.Add "FileUnits", "Millimeters"
Call oDwg.Open(oData, oContext, oOptions, oDoc)
End Sub
