At least have a pop up when you export asking if you'd like to save first.

If auto save is added, please make it a selectable preference. I often like to open a file to play with ideas, then exit without saving if the ideas don't work. I'd wouldn't want auto save to make a simple experiment permanent.

I have to say I didn't realize auto-save was NOT a feature. Seems obvious that it ought to be.

Yes. Good

Yes this is a must! I've definitely run into a problem where doodly failed and I lost the progress on my work.

Autosave should be set on a timed basis for all files Doodly files so that if and when the platform fails - which seems to happen at random - the work can be recovered. It would be fine to have a preference whether the autosave file is deleted upon deletion or exit without saving. But PLEASE, if the platform is going to be unstable, have an autosave feature. This should have been part of the original architecture.