public class Hwnd32 : System.Windows.Forms.IWin32Window
    {
        private IntPtr m_hwnd;

        public Hwnd32(IntPtr handle)
        {
            m_hwnd = handle;
        }

        public IntPtr Handle
        {
            get { return m_hwnd; }
        }
    }

    public class TestExporterDescriptor : ClassDesc2
    {
        private IGlobal m_global;
        private static IClass_ID s_classID;

        public TestExporterDescriptor(IGlobal global)
        {
            m_global = global;
            s_classID = global.Class_ID.Create(8264, 9283472);
        }

        public override string Category
        {
            get { return "Max.NET Test Exporter"; }
        }

        public override IClass_ID ClassID
        {
            get { return s_classID; }
        }

        public override string ClassName
        {
            get { return "TestExporter"; }
        }

        public override object Create(bool loading)
        {
            return new TestExporter(m_global);
        }

        public override bool IsPublic
        {
            get { return true; }
        }

        public override SClass_ID SuperClassID
        {
            get { return SClass_ID.SceneExport; }
        }
    }

    public class TestExporter : SceneExport
    {
        private IGlobal m_global;

        public TestExporter(IGlobal global)
        {
            m_global = global;
        }

        public override string AuthorName { get { return "Chris Wood"; } }
        public override string CopyrightMessage { get { return "Copyright 2009 MWL"; } }
        public override int ExtCount { get { return 1; } }
        public override string LongDesc { get { return "Test Exporter using Max.NET SDK"; } }
        public override string ShortDesc { get { return "Test Exporter"; } }
        public override uint Version { get { return 1; } }

        public override int DoExport(string name, IExpInterface ei, IInterface i, bool suppressPrompts, uint options)
        {
            MessageBox.Show(new Hwnd32(i.MAXHWnd), "TestExporter.DoExport() called");
            return 1;
        }

        public override string Ext(int n)
        {
            return "SMS";
        }

        public override string OtherMessage1()
        {
            return String.Empty;
        }

        public override string OtherMessage2()
        {
            return String.Empty;
        }

        public override void ShowAbout(IntPtr hWnd)
        {
            MessageBox.Show(new Hwnd32(hWnd), LongDesc, "About " + ShortDesc);
        }
    }

From the Autodesk Error report:

"Application: 3ds Max    Version: 3ds Max 11 - 64 bits       Error: Unhandled Exception"

Attached image of error dialog from Max before it closes itself.

---

Attached Files:

I get exactly the same result in Max 2009 32-bit and 64-bit versions. Basic geometry and utility plugins appear to work correctly.

Any progress on this?

This one can wait. I can just write my stuff as a Utility for now.