Why do I get a message "Exception: Not_that_many_bytes_left"?
The message will appear when trying to export or batch export an empty sequence as Quicktime reference and "Mixdown Audio Tracks" in the Export's options panel is activated.
If it appears when trying to import a .wav file, load the file in question with the Windows Sound Recorder (available fom the Windows Start Button) or another audio editing application and save it again as .wav file.