Minecraft was always rooted in ancient days of fantasy. You started out with nothing, you dug in the ground for minerals and you built things out of blocks. The only proper "vehicles" are mine carts that run on tracks, and soon horses will be introduced that you can ride. The thing you cannot do natively is build moving objects with blocks. MoveCraft overcomes this. It isn't fast, and it isn't always pretty, but it works.
On the Server Setup page you made a spaceship.craft file. This file defined the list of blocks that can be part of a moving "craft" called "spaceship". Later you can stop your server, edit that file to add more blocks to the list and restart your server if you want to make fancier spaceships. You can also make new files with other names to make more spaceships. For complete details see the Movecraft page.
Here we will just make a flying saucer.
A spaceship is just any object that is made with only blocks contained in the ".craft" file that is associated with it. If you use other blocks, they won't move, either being left behind when you move or trapping your ship. Getting told your ship is obstructed no matter what you try is a good sign you used a wrong block.
Our file just contains stone and glass, so I've made a small flying saucer here with just stone and glass.
What makes it a "Movecraft" is that you create a sign on the ship somewhere with the "type" as the first word on the sign. So here the sign says "spaceship" right across the top.
To pilot your craft hold a stick in your hand and right click on the sign with it. You should get a message saying that you have "Successfully piloted craft!"
Now to move around just right click in any direction with the stick still in your hand. Your ship will move in that direction if possible. If you run into something you will be told that you cannot move.
When you want to quit flying the ship, just move away from it sufficiently and you will be told that it will be "released" shortly.
Here you can see the small flying saucer has moved away from the "space station".
Here are some more pictures of the little craft heading toward the blue planet and then landing on it.
Please take a look at my gallery for pictures of more of the spaceships my family has made.
Because it is hard to understand this concept with still pictures, here is a short video of me using MoveCraft in my space world.
Finally let's look at how to make portals with MultiVerse ->