Can I load up an existing base game save in Spaced Out?
No, saves from the DLC and base game are not compatible with each other. You will need to start a new colony when you begin Spaced Out, and won’t be able to load any colonies played in Spaced Out back in the base game.
What if I want to go back to the base game?
You can manage the DLC using your Steam library the same as other games, or use the toggle in the corner of the main menu.