Yes, the Spirit patch has really broken the old Save games as I have now found multiple things not working at all.
So old Saves are useless and thus current games cannot be completed. So nice of Paradox/Heimimont to warn us about Save game compatibility. And Steam will not let you go back to a previous version either. I really HATE the way Steam forces you to update games and then everything breaks.
Thankfully I have a partition backup from the weekend and reloading the old Surviving Mars folder into Steam from the backup and forcing Steam into offline mode so it cannot update has enabled me to continue playing my old game with the previous version.
Why can't we be allowed to finish "old" games in Surviving Mars as you can with Steam for many other Paradox Games like EU4 and others?
Rob