The sandbox mode now has custom gameplay settings, for now it is just a few ones including never needing to eat or infinite building materials and some sliders. But as we plan to implement new hardcore elements like food rotting and starvation this page will get filled with new options as we progress.
You can access it by starting a new game or change it in the game settings, these options are not saved globally like the other settings, they are save-based.
We found a few more building-based bugs, we will be releasing a new patch to fix them soon as well as adding new chests, shelves and adding inventory capacity to a few existing pieces.