In VBA how to determine if shape have some reference?

Need help to solve that thing...

1. I take ByRef s As Shape in one of my functions. The shape contain some curves that need to be extracted one by one. So...

2. I extracting curves trough my another function, sience corel vba shape.Extract(OldReference) function is not properly documented and not working good, my function is:

Function ExtractSubpath(ByRef FromShape As Shape, ByVal Index As Long) As Shape
' return extracted subpath as separate shape and delete it in original shape
' and leave referencies for original shape
Set ExtractSubpath = ActiveLayer.CreateCurve(FromShape.Curve.SubPaths(Index).GetCopy)
With ExtractSubpath
.OutLine.CopyAssign FromShape.OutLine
.Fill.CopyAssign FromShape.Fill
End With
FromShape.Curve.SubPaths(Index).Delete
End Function

3. My ExtractSubpath function is working fine, but when last subpath is deleted - the shape s lost all referencies. My question is:

How to determine if shape s have some reference?

For example I've tried to check in such ways "If s.Curve.SubPaths>0 Then <do somthing>..." and "If Not s Is Nothing Then <do somthing>..." , but there an error... below is what hapens in watch before attemting to check s:

Watch :   :    s.Curve.SubPaths : <The referenced object no longer exists in this document.> : Integer : agWeb.BevelCurve

Thanks... Hope my english is good enough to understand me.