Everything that adds pips to the Doom Counter should now add no pips at all, everything that removes pips should remove a hundred at once, the Doom Counter is a hundred pips long instead of twelve or so, and the time between those pips not being added should now be vastly increased.
To install, unpack the .rar file into your "XCOM 2\XCom2-WarOfTheChosen\XComGame\Mods" folder.