PowerPoint Automation and Saving as HTML

Up until Office 2010, our application could save a PPT or PPTX file as HTML from C/C++ code.  With 2013, this is failing:

int saveAsHTML(CComPtr<PowerPoint::_Presentation> presentation, TCHAR *destDir, TCHAR *imagePrefix)
{
    CComPtr<PowerPoint::WebOptions> webOptions;
    HRESULT hr = presentation->get_WebOptions(&webOptions);
    TCHAR slideName[256];
    swprintf(slideName, _T("%s%s%s.htm"), destDir, SEPARATOR, imagePrefix);
    // Save copy of file.            
    BSTR szSlideName = T2BSTR(slideName);
    hr = presentation->SaveCopyAs((BSTR)szSlideName, ppSaveAsHTML, msoFalse);
    SysFreeString(szSlideName);
    if (hr != S_OK) return 1;            
    return 0;
}

The above code works in PowerPoint 2007 & PowerPoint 2010.

This is an abbreviated but still tested piece of code from our product.

In 2013, the above call to get_WebOptions() is returning NULL while in previous versions it was not.  If the return is NULL, the function would have immediately returned with an error.

The call to SaveCopyAs() is given a parameter for saving as HTML.  The return value is FFFFFFFF80048240.  I have looked this up and found this MS Support KB number 285472.  (I'd include the link but I don't want my posting delayed while my account is verified.)

The error code is specific to PowerPoint.  The workaround mentions making the following call:

PowerPoint.Application.Visible = msoTrue

I found this interesting since PowerPoint is visible.  I also found it interesting that our code has already been making this call:

	CComPtr<PowerPoint::_Application> objApp;
	HRESULT hr;
	hr = ::CoCreateInstance( __uuidof(PowerPoint::Application), NULL, CLSCTX_LOCAL_SERVER,
        __uuidof(PowerPoint::_Application), (void**) &objApp);
	if (hr != S_OK) {
		errorOut(_T("CoCreateInstance"), hr, objApp, NULL);
		return 1;
	}
	objApp->put_Visible(msoTrue);

I'd like to know if this is an existing issue with 2013, whether saving as HTML is still supported or if there are any work arounds.