I was using the lego mindstorm classroom program that has scratch built in, so I'm not sure of the exact details. It autosaved the project on every change, and didn't even tell me where it was keeping the files. The first time I was using it, it suddenly told me it couldn't open my project. So I found the save folder and just duplicated my recreated project as I went along. Not an ideal workflow, but fine for a few hours project.