1. Close the game
Do not copy active save data while the game is running. Close the application first so that it is not still writing progress.
2. Find the current save
Identify the folder or files that contain the actual progress. Do not assume the game's installation directory is where saves live.
3. Create a separate backup
Copy the working save to another location before attempting the transfer. Keep that copy unchanged.
4. Prepare the destination
Confirm that the destination installation is the version and platform you intend to use. Compatibility problems are easier to diagnose when only one variable changes at a time.
5. Copy the save
Place a copy of the known-good save into the destination's expected save location. Avoid deleting the original at this stage.
6. Test before cleanup
Launch the destination, load the save, and check important progress. Only after a successful test should you consider cleaning up duplicate files.