I have no issues with ruptureId being optional; but I would also accept a mandatory ruptureId, always equal to 1 in the scenario cases, since there is a single rupture there. That would make the XML output uniform and it would make it simpler to parse the GMFs coming from different calculators. What do you (or Vitor) think? Same for stochasticEventSetId. Other than that, it LGTM.