Nero SDK Ripper

I am trying to create A Nero GUI Application for ripping audio track to wave files. I am getting return code 1, instead of 0 for NeroDAE API call. Anybody has a clue ? I am using VC+ 6.0 on Windows 2000 system.
I am able to rip using the command line application.

Added an idle callback in the Progresscall back function. It started working.

BOOL NERO_CALLBACK_ATTR MyAppln::ProgressCallback(void pUserData, DWORD dwProgressInPercent)
{
// the NeroAPI updates the current progress counter
((CBatchEncoderDlg
)pUserData) ->m_pgrProgress.SetPos(dwProgressInPercent);

return IdleCallback (pUserData);

}

What is the SDK licence fee?