An utterly unrealistic sailing vessel designed to squeeze as much as physically possible out of just sail power and to look good while doing it, without taking much skill or effort to make or use.
The main thing you'll be surprised by if you load this up will be that there are sails on the bottom of the ship. These actually work, and are the primary way the ship stabilizes in heavy (read: anything above a stiff breeze) winds.
To deploy the bottom masts, find a spot in the sea deep enough for them, and then press the marked button next to the helm.
Once these bottom sails are active the ship is much more stable and can handle some pretty extreme winds, but still take care with it. It's not as robust as a diesel ship, that's for sure. See screenshots for actual images of this thing surviving tsunamis and extremely rough waves.
The bottom sails can get stuck when you try to fold them back into place. Do not do so under high winds, and make sure to face them directly forward with sails fully furled before pressing the button to fold them back in. It may take multiple presses to get them to do anything. Even then, they can get stuck out due to the wind pulling the pivots they rely upon out of their sockets.
The Moonshadow is not a very good ship for search and rescue, fishing, delivery, or anything other than having a relaxing and fun cruise around the map. Even with modest winds it can take hours to deliver a package, during which you will have to micromanage the masts based on wind direction as this is not fully automated (I consider it part of the fun of sailing). There are some minor protections, though: the sails should automatically slowly furl if the ship is going backwards, and there is a heading hold for the rudder.
There is a gangplank on one side of the ship which you can use as a makeshift crane and to somewhat attach to other ships. Use the nearby handle to control it.
The sails all operate the same way and the masts are all controlled with the same buttons. So, you can't perform particularly advanced sailing moves like turning in place, but the controls are very simple and should be self-explanatory, I think.
In the event you want to refuel another ship, there is a diesel tank in the center of the ship which you can pump out from, and a two-way manual pump on one railing. Attach the hoses properly and you can pump fuel whichever way you please.
There is also space to put fish if you feel like manually fishing during dead winds.
Technically, this thing was partially modeled after the AC4 Jackdaw.
Have fun sailing the seas!