Как из VBA вызвать стандартное окно диалога AutoCAD?

(setvar "filedia" 1)
(setq fn (getfiled "Выбор файла" "" "txf" 4))
(setvar "users1" fn)
(vl-vbarun "importTXF")

Public Sub ad_OpenDialog()
Dim adApp As AsdkUNSUPP2000Lib.Application
Dim adFileOpen As String
Set adApp = Application.GetInterfaceObject("Asdkunsupp2000.Application.1")
adFileOpen = adApp.ShowOpenDialog("File Open Dialog", "c:\_jobs\", "dwg")
MsgBox adFileOpen
End Sub 

Private Type BrowseInfo
     hwndOwner As Long
     pIDLRoot As Long
     pszDisplayName As Long
     lpszTitle As Long
     ulFlags As Long
     lpfnCallback As Long
     lParam As Long
     iImage As Long
End Type
Private Declare Function lstrcat Lib "kernel32" Alias "lstrcatA" (ByVal lpString1 As String, ByVal lpString2 As String) As Long
Private Declare Function SHBrowseForFolder Lib "shell32" (lpbi As BrowseInfo) As Long
Private Declare Function SHGetPathFromIDList Lib "shell32" (ByVal pidList As Long, ByVal lpBuffer As String) As Long
Private Declare Sub CoTaskMemFree Lib "ole32.dll" (ByVal hMem As Long)
Dim FolderDialogTitle As String
Dim ShowDirsOnly As Boolean
Dim hwndOwner As Long
Sub ВыбратьДиректорию()
hwndOwner = Me.hWnd
FolderDialogTitle = "Select Directory"
ShowDirsOnly = True
MsgBox ShowFolder
End Sub
Function ShowFolder() As String
Dim lRes As Long
Dim sTemp As String
Dim iPos As Integer
Dim bi As BrowseInfo
With bi
    .hwndOwner = hwndOwner
    .lpszTitle = lstrcat(FolderDialogTitle, "")
    .ulFlags = Abs(ShowDirsOnly)
End With
lRes = SHBrowseForFolder(bi)
If lRes Then
    sTemp = String(MAX_PATH, vbNullChar)
    SHGetPathFromIDList lRes, sTemp
    CoTaskMemFree lRes
    iPos = InStr(sTemp, vbNullChar)
    If iPos Then sTemp = Left(sTemp, iPos - 1)
End If
ShowFolder = sTemp
End Function