[Solved] m_bDrawSingleTab

I've modified the MDIPanes sample as followed:

    // Create docking panes.
    CXTPDockingPane *pPane1 = m_paneManager.CreatePane(
        IDR_PANE_PROPERTIES, CRect(0, 0,210, 120), xtpPaneDockLeft);
   pPane1->SetOptions(xtpPaneNoCaption | xtpPaneNoFloatable);

    CXTPDockingPane *pPane2 = m_paneManager.CreatePane(
        IDR_PANE_PROPERTIES, CRect(0, 0,210, 120), xtpPaneDockLeft);
   pPane2->SetOptions(xtpPaneNoCaption | xtpPaneNoFloatable);

   int nID = IDR_PANE_PROPERTIES;
    m_paneManager.SetIcons(IDB_BITMAP_ICONS, &nID, 1);

    m_paneManager.SetTheme(m_themeCurrent);

   m_paneManager.AttachPane(pPane1, pPane2);

   m_paneManager.HideClient(TRUE);
   CXTPDockingPanePaintManager *pManager = m_paneManager.GetPaintManager();
   pManager->m_bDrawSingleTab = TRUE;
   pManager->GetTabPaintManager()->SetPosition(xtpTabPositionBottom);

If you start the app it will look like this:


You can now split it vertically:



But if you dock the pane on the left and then on the top, the tab is gone!!!