To put the Assassin's Creed map in your Minecraft, do this:

For Windows: 

Press Windows Key+R at the same time.  This will bring up a window that says Run.  Type in: appdata.
Then click Ok.  Click the Roaming file.  Then, click the .minecraft file.  In this file, scroll down until you see a
saves folder. Click it.  Inside, are the worlds you've made (or downloaded).  Drag the Assassin's Creed map folder into 
the saves folder.  Now you're all set, have fun!