I've started playing Stranded Deep again on Steam. I'd like to know how to add new islands through the community? When I try to access them in-game, it says I'm not subscribed to any community content.
While NOT in the game itself, in Steam, Stranded Deep, Click on “Discussions”, then “Workshop”. You can “Browse”, “Items” and see islands there.
Unsure if this link will work but, this would (for example) show all of robertmonkey islands: Steam Community :: robertmonkey :: Workshop Items
Once you have clicked on the green "+” to subscribe to an island, your computer will automatically download the map.
Then, when you launch Stranded Deep, and go into the cartographer, you will see those subscribed islands, and can drag/drop them over any existing island in your world, to replace it. Just be careful not to replace an existing island that is your ‘main island, where you have built your castle’. That would be sad.