AutoCAD VBA Close Spline

[SGF1]

I have successfully drawn all the splines I need in a project and now need to close them. VBA help says this property is read-write, but when running the program the line (object.closed = true) returns a "read-only property" message. VBA Help says splines are accessible via a selection set, which I have tried without success (coding problem perhaps). I haven't been using VBA in AutoCAD long - previously have used script files successfully, generated from Excell VBA, but now need more functionality. Would appreciate any help.