For new players, here are some tips and tricks to get you started:
Installing version 1.05 is completely safe for existing save files. It will automatically upgrade your save data to the new version format. However, note that once a save file is updated to 1.05, it cannot be read by older versions of the game (e.g., rolling back to 1.04). Why You Shouldn't Skip This Update
Which you are playing on (Console CFW or Emulator)?
Understanding the Unicorn Overlord Update 1.05: Features and NSP/JPN Versions