Ok so, (1) most embassies have totally different time slots for non immigrant vs immigrant visa interviews (for example one kind in the mornings and the other in the afternoons) - and the summer crush you talk about I am sure is for tourist visas? And (2) DV is the only immigrant visa that is time sensitive, so if any visa appointments do have to be postponed due to workload it will be other types, not DV. In any case I believe the immigrant visa caseload at Madrid is pretty small.
I don't think tourist visas (Spaniards don't neet a visa for visiting the US as tourists),....most likely 90% will be students and J1-visa applicants.
Thanks for teh clarification, it makes more sense seperating non-immigrants from would-be-immigrants.
Just one last question if you don't bother,...what passport should i give them? My moroccan passport? My spanish passport? or both?