A: Possibly, but not recommended. Use the included save cleaner. Bugs like the missing Despair Cog are fixed retroactively, but the elevator softlock might still trigger if your save is past a certain flag.
Do not paste files directly into the inner game folder unless specified; paste them into the root directory to overwrite naturally. Deep structural code changes between versions. metf chapter 3 patched
However, some in the competitive scene have expressed concerns that [specific change] might make the game too slow. Nevertheless, the consensus is that the game is now in a much healthier state. A: Possibly, but not recommended