Hey ETW community
I think I've come a cross a simple fix for some campaign crash issues. Over the past few months I've been experiencing crashes when the AI is about to end its turn, or when loading from certain savegame files. I looked into the issue and figured out that the problem seemed to occur after the game attempted to create a new autosave. After looking in vain for a solution, I've found one so simple that I can't believe I didn't think of it sooner.
Go to your ETW save game directory once you've started a new campaign. Make sure a valid, uncorrupt autosave file has been produced. Right click and go to propertie, then set the autosave to READ ONLY and click apply. Apparently this prevents the game from overwriting autosave files.

So far this fix has worked for me and I haven't experienced a savegame related CTD since. note that this won't save your already corrupt files; it only prevents future savegames from being corrupted.

I hope you find this helpful. Please leave some feedback once you've tried the fix for yourself.