The released update on Dec. 15th changed the location of Dedicated Server's save data and setting files to the same directory as "Craftopia.exe" from the "AppData" directory.
Please manually move the Dedicated Server's save data and setting files to the same directory as "Craftopia.exe" if you've ever hosted Multiplayer with the Dedicated Server.
Sorry for the inconveniences and thank you for your sincere understanding.
Craftopia Development Team