D stands for demand. This is not a request, got it Peppy? 
Toggle on/off, maybe in song setup, or somewhere in the editor. If enabled, the loaded map will auto every 60 seconds. Autosaves will (should) be saved to a different file, such as map.osu.bak or something. Additionally, this autosave file will be removed upon manually saving.
Sure, maybe you don't want 'accidental' changes being auto-saved, that's fine. Auto-save will never directly overwrite any .osu file. When you're mapping, auto-save will save anything you've done to a temp. file every 60 seconds. Should you crash, or exit the editor without saving, that data remains in the temp file. Should you manually Save (CTRL+S), the data in the temp. file will be applied to the .osu file.
Additionally, in the editor, in the file menu, there would be an option to 'load backup' or 'load autosave' should you have crashed or exited without saving.
Toggle on/off, maybe in song setup, or somewhere in the editor. If enabled, the loaded map will auto every 60 seconds. Autosaves will (should) be saved to a different file, such as map.osu.bak or something. Additionally, this autosave file will be removed upon manually saving.
Sure, maybe you don't want 'accidental' changes being auto-saved, that's fine. Auto-save will never directly overwrite any .osu file. When you're mapping, auto-save will save anything you've done to a temp. file every 60 seconds. Should you crash, or exit the editor without saving, that data remains in the temp file. Should you manually Save (CTRL+S), the data in the temp. file will be applied to the .osu file.
Additionally, in the editor, in the file menu, there would be an option to 'load backup' or 'load autosave' should you have crashed or exited without saving.