Ziehe auf die DLL DGMask das Benutzersteuerelement DGRahm as DGRahm1.

'Code in DGMask:
Public pRahmenGrid As DGRahm
 
Private Sub dg_mask_CellBeginEdit(...)
 
 Dim rect As Rectangle
 rect = dg_mask.GetCellDisplayRectangle(dg_mask.CurrentCell.ColumnIndex, 
        dg_mask.CurrentCell.RowIndex, False)
 RahmenGrid_Anbindung_anstossen(rect.Y, rect.X)
end sub
 
Public Sub RahmenGrid_Anbindung_anstossen(ByVal RTop As Integer, ByVal RLeft As _
  Integer)
  DGRahm1.RahmenGrid_anzeigen(RTop, RLeft)
End Sub

Code im DGRahm:
 Public Sub RahmenGrid_anzeigen(ByVal RTop As Integer, ByVal RLeft As Integer)
     With dg_Rahmen
       .Top = RTop
       .Left = RLeft
 
       .Visible = True
       .BringToFront()
     End With
 End Sub