This might be late, but nobody mentioned RUN AS ADIMINISTAROR. To be very specific:

1 Run from a short cut with admin.
2. i;'m on windows 10 home
3. i usually use F1 for quick save.

Hope that helps this save crash can discougage people from playing this awesome game!~
This game is very special.

I just realised that this was reported for the case when using ESC to save the game. The problem is actually just a wonky user interface - ESC is used to quit the game and the game also lets you choose to save before you quit. You get the same prompt when you select "EXIT TO DOS" from the in-game menu.

To avoid it, use TAB to bring up the menu and select" LOAD/SAVE GAME"

See the attached screenshot where I used ESC to bring up the menu - notice the heading says "EXIT: SAVE GAME?". It would have been better if they had labelled the option "SAVE AND QUIT" instead of just "SAVE".