The configuration setting affects the interval for new games. To disable it in your current game you need to set it with :S. Also, attaching a zip of one of your save files would probably be helpful for the devs.

Thanks for the tip, Grond. It turns out that disabling the autosave doesn't stop the game from crashing. Instead the game just crashes.

I note that even when I manually save, the game quits (crashes?) after saving without returning to the main menu. The configuration file says quit after save = false.

I have uploaded the latest svg file which crashes along with an old autosave file that was generated before the game started crashing.