Locating your game save files is fairly straightforward. Just follow these steps:

1. Open the Roaming Folder
   This is a hidden folder inside your user directory. The easiest way to get there is to type %appdata% (with the percent signs) into the Windows search bar or the Run dialog (Win + R). This will open the Roaming folder.
   
   
2. Backtrack to AppData
   Once in Roaming, go up one level to the main AppData folder. You should see three subfolders: Roaming, Local, and LocalLow. Open the Local folder.
   
   
3. Find the Game Folder[
   Inside Local, look for a folder called DropDuchy.
   
   
4. Navigate to Save Files
   From there, go to:
   Saved → SaveGames → Users
   
   
5. Locate Your Save File
   In the Users folder, you’ll see two folders: Main and Main_backup (followed by a string of numbers). Open the Main folder.
   Inside, you'll find a file called ProgressionSave.sav — that’s your game save.

And that’s it! You’ve found your save file. You can back it up, share it with a friend, or replace it with someone else’s save if needed.

Note: I’ve tested this process myself, it works. No need to mess with the backup folder. I have not tested things like different operating systems or versions (14-06-2025).

If you know how this stuff works, then here is the filepath, just change out [NAME]:

C:\Users\[NAME]\AppData\Local\DropDuchy\Saved\SaveGames\Users

Here, in the folder with main at the end, you find the ProgressionSave.sav file, which is the file that you need.

If you want to experience all the features without having to complete the challenges, you could replace your current save file with a completed one.
To do this just follow the guide above.

A completed save file can be found here:
https://www.speedrun.com/Drop_Duchy/resources

Speedrun.com resources contains at least one game file which I have uploaded myself. In the future, maybe other game files can be found there as well.