Installing a downloaded save file is straightforward, but it varies slightly depending on your version (Uplay vs. Steam).
Always copy your Orbit or Savegames folder to your desktop before messing with files. Locate the Folder:
In this guide, we’ll break down how to find these saves, how to install them, and which milestones you should look for to get the "best" experience. Why Use Mission-Specific Save Files?
C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\savegames\[Account ID]\856
This is the most popular save. It starts right after you’ve completed the first few missions for the Golden Path.
Delete the existing .save files in the folder and paste the new ones you downloaded.