Crash when filesave size reaches 32MB

At a gamesave filesize of 32MB, the game will end abnormally (abend), collect data to send to microsoft?!, and restart the computer.  

I have checked for graphics updates.   Microsoft removed "compatability", so I can't set the game to run as admin.   

The fact that the problem is a 32MB save size is an intuitive observation.   After repeated efforts to get the size larger, I once noticed that it reported a size of 41MB, the screen flashed and it then reported 32MB, then it saved.   One time it was so bad that an entire chunk of an area where I did a lot of building was reset to spawn state.  I suspect that has happened in other crashes, but I don't know which chunk was respawned.

So now, I can't play on my own PC minecraft world.