I've got a macro that is supposed to flatten a sheet metal part, but every now and then I get a part that it doesn't work on. I'm trying to debug it so I can add in some error handling, but I can't figure out what is causing the problem. Here's the code I'm using, seems to be pretty universal. After the rebuild line, the part has an extra Sheet-Metal# & Flat-Pattern# in the design tree that are unsuppressed, but the Flat-Pattern-1 feature, which contains bends, is still suppressed. Any insight?

Sub Flatten()
    Dim swApp               As SldWorks.SldWorks
    Dim swModel             As SldWorks.ModelDoc2
    Dim nBendState          As Long
    Dim nRetVal             As Long
    Dim bRet                As Boolean
    Set swApp = CreateObject("SldWorks.Application")
    Set swModel = swApp.ActiveDoc
    nBendState = swModel.GetBendState
    Debug.Print "File = " & swModel.GetPathName
    Debug.Print "  BendState    = " & nBendState
    If nBendState <> swSMBendStateFlattened Then
        nRetVal = swModel.SetBendState(swSMBendStateFlattened)
        Debug.Print "  SetBendState = " & nRetVal
        ' Rebuild to see changes
        bRet = swModel.EditRebuild3: Debug.Assert bRet
    End If
End Sub