Just wanted to post the fix from CineForm support since I couldn't find this error on line when searching for it.

Error: CreateAndAddFilter(CLSID_DIVX_MPEG_Demux, pSplitterName, &mediaSplitter) (0x80040154 - Class not registered) in (ConvertGraph.cpp at 2757)

Fix:

Make sure you are logged in as an admin and turn off user account control in windows control panel. After turning off UAC, restart the computer.

Then browse to c:\program files (x86)\common files\cineform\

Then double click on the file called 'mc_demux_mp2_ds.ax'.

If Windows asks you how to open the file, browse to c:\windows\system32\ and select 'regsvr32.exe'.

You should get a message saying the file successfully registered.

Now reconvert your files and it should work.