In my understanding, these votes that they are picking up are the discarded void ballots which had crayon marks outside the box and earlier counts led them to be discarded, and now AMLO has convinced the IFE that the people WERE trying to vote PRD, and their pencil marks went outside the box. Like hanging chad, pregnant chad stuff.
Yes rovenstinez, that is what I am reading too. In Cuernavaca the local PRD representative was very angry that the magistrate would not count more null votes for AMLO. In Veracruz evidently the magistrate was pro-PRD, so I think we can expect to see some "subjective" evaluation of null votes creating the differences.