The game will report a successful save but it doesn't actually create a save file. The in-game list remains empty and the directory where the saves should go does not yet exist.
Neither does the game save my graphics preferences. I turn on 'fullscreen window' but each time I restart the game it's back on 'fullscreen.'
I've moved the game to another drive because perhaps it didn't have write privileges in the administrator locked SSD, but that didn't solve the problem.

My OS version is Windows 10 Education 64-bit (10.0, Build 18363) (18362.19h1_release.190318-1202)
My game version is 1.5229.951665