Every time Stinky lands his rocket and triggers a suffocating warning, the game client freezes. It is unresponsive and I waited approximately minutes during the first crash before reloading the game. I managed to fix the issue by rushing to the gantry and opening a path for Stinky to route to oxygen.
No need to do anything once you have opened the save file. Once Stinky has landed his rocket and a suffocating warning triggers, the game client freezes.