I was going to post a review of the demo, but then I tried to review everything in great detail and it was becoming very long. I would be probably be better off saving that energy for the testing. For all I know, everything I was going to complain about has already been fixed in Frontier. My second try is much shorter.
Overall, this game seems to be aiming to be a simulator of a small Mars colony. Not an established colony, but one that you are helping to build and bring online. It is a game where the environment is not hospitable to you, where the only protection from the environment is your EVA suit and the colony itself. The colony itself provides long term survival, allowing you to produce water, food, oxygen, fuel for your rover, etc; as well as a safe place to take off your EVA suit and recover. Between the EVA suit and the rovers, you have considerable mobility outside the base, with the inevitable increase in hunger, thirst, radiation, and consumption of fuel being the reasons to return home.
Much of the equipment you get in game appears to have been built to be robust and stupid simple, not complex and automated. There are no hardware stores you can travel to get equipment fixed or replaced. No computer technicians to fix your computer problems. Consequentially, you should expect to need to turn things back on from time to time, be cleaned on occasion, or be repaired every so often. You will often need to carry things around your base, such as water containers to water your plants, or bring food back to the freezer.
One should keep in mind that this demo appears to have been made before the game was complete. So bugs like being unable to make nutrients for worms or mushrooms, or losing important items when attempting repairs, are to be expected. Sometimes this can break the game, making it difficult to do anything else in the game. I found that I could start things over by uninstalling and reinstalling the demo. This will delete all progress, so you will start playing again as though you never played before.