i searche and didnt find it. i dont know why this hasnt been suggested honetly. i jjust lost a map ive spent around 5 hours making. i think there should be an autosave function or at least a key combo to quicksave the work thats been done in the editor. just a suggestion :)
almost certainly not going to happen for this game, but if you put an editor autosave suggestion in the game 3 suggestions forum it might make it in there (may be in there already) ;)