Find it here: http://www.stonehearth.net/dt-re-embarkation/
Also, just as the builder hit unstable last week, Multiplayer is now available to play on it's own special unstable branch. Head over to this link for details:
https://discourse.stonehearth.net/t/its-happening-multiplayer-available-on-another-super-unstable-steam-branch/34827