I know that this game crashes when exiting sometimes.
It seems that this bug exists from v1.18 (01/14/2018).
On v1.18, I switched the build method from 'mono' to 'il2cpp'.
The reason why I switched is that 'il2cpp' is more compatible than 'mono'.
However, it seems that 'il2cpp' is unstable for this game.
So from this version (v1.25), I decided to switch back to 'mono' and publish 'il2cpp' version as a beta (You can select in BETAS tab).
If the game doesn't start at all, try 'il2cpp' beta.
Please see instruction in this FAQ.
Other changes
Many players couldn't notice how to save and load, so I added instruction text about save and load menu.