CXTPDialogBase<CXTResizeDialog>

in OnInitDialog create your commandbars

// Initialize the command bars
	if(!InitCommandBars())
	{
		return -1;
	}	
 
	// Get a pointer to the command bars object.
	CXTPCommandBars* pCommandBars = GetCommandBars();
	if(pCommandBars == NULL)
	{		
		return -1;      // fail to create
	}
 
	
 then create your ribbon:

CXTPRibbonBar* pRibbonBar = (CXTPRibbonBar*)pCommandBars->Add(_T(""), xtpBarTop, RUNTIME_CLASS(CXTPRibbonBar));
 
	if (!pRibbonBar)
	{		
		return FALSE;
	}

	pRibbonBar->EnableDocking(0);
	pRibbonBar->EnableCustomization(FALSE);
...
 
	CXTPRibbonTab* pTabBase = pRibbonBar->AddTab( CMfxString(IDS_RIBBON_START) );
... 

you will nedd a helper

//--------------------------------------------------------------------------------------- 
void CDlgMailNew::RepositionControls()
//--------------------------------------------------------------------------------------- 
{
	if (m_bInRepositionControls)
		return;
 
	CRect rcClientStart;	
	GetClientRect(rcClientStart);
 
	if ((GetStyle() & WS_MINIMIZE) || (rcClientStart.IsRectEmpty()))
		return;
 
	m_bInRepositionControls = TRUE;
 
	CRect rcClientNow;
	RepositionBars(AFX_IDW_CONTROLBAR_FIRST, AFX_IDW_CONTROLBAR_LAST, 0, reposQuery, rcClientNow);
 
	CRect rcBorders(rcClientNow.left - rcClientStart.left, rcClientNow.top - rcClientStart.top,  rcClientStart.right - rcClientNow.right, 
		rcClientStart.bottom - rcClientNow.bottom);
 
	if (rcBorders != m_rcBorders)
	{		
		CPoint ptOffset(rcBorders.left - m_rcBorders.left, rcBorders.top - m_rcBorders.top);
		CSize szOffset(rcBorders.left + rcBorders.right - m_rcBorders.left - m_rcBorders.right,
			rcBorders.top + rcBorders.bottom - m_rcBorders.top - m_rcBorders.bottom);
 
		m_ptRepositionOffset = ptOffset;
 
		CRect rcWindow;
		GetWindowRect(rcWindow);
		rcWindow.BottomRight() += szOffset;
 
		Offset(ptOffset);
		m_szWindow += szOffset;
		m_szMin += szOffset;
	
		MoveWindow(rcWindow, TRUE);
	}
 
	m_rcBorders = rcBorders;
 
	RepositionBars(AFX_IDW_CONTROLBAR_FIRST, AFX_IDW_CONTROLBAR_LAST, 0);
	
	m_bInRepositionControls = FALSE;
}

----

call this helper in OnSize and in OnInitDialog

:-)