I just upgraded from VV3 to VV4. I also have SF5.0h and the batch converter on my machine. After loading VV4, the batch converter is asking me for a serial number. I gave it my SF5, VV3, and VV4 serial numbers but none of them will work to register the Batch Converter.
I think the batch converter has its own serial.
Nevertheless - I also think the batch converter is redundant in Version 4 because you can do very comfortable batch converting via Vegas scripts.