If you use the Shovel button on a water tile, you can create a new piece of land. This is essential for progressing in the game, but in hindsight we didn't explain this clearly enough.
We'd love for you to give our game a second chance, and perhaps update your rating if it affected your enjoyment. In any case, thank you for your feedback and for playing!
EDIT: we have added it as a tip to the top of our game page's description. Hopefully this will help out other players as well :)