You should be able to prepare PowerPoint slides form any standard case that you may receive (or give). It's quite similar to a "normal" case with the difference being that you have to overtly define priorities, develop a small number of very directed hypotheses, and devise an evidence-based conclusion. With those pieces, then you structure your presentation with the appropriate logic.
Not completely gratifying, I know. If you're crunched for time, try looking for late round cases used for Bain and L.E.K. interviews. There should be material in line with - what I think - you're looking for.
Hope that helps.