Perhaps the ability to save a scenario for later revisitation was added with the latest update, but it wasn't publicized, and it doesn't show up in settings, etc. Is it inconspicuously resident somewhere? Its apparent on-going absence while the updates emphasize graphic enhancements suggest to me that perhaps the developers are steering more towards a game (albeit a very nice one) than a rigorous home simulator that one could credibly gain valuable experience with, trying different approaches to difficult situations without starting entirely from scratch.