Using the interface...

You can drag the interface box around. Move it into the ocean!
Jump to a date by typing it in over the current date (jumping backwards not supported).
Click play/pause to start/stop the simulation.
Click on the "By Month" button to adjust the playback speed.
Hover over a province to see the province/owner name.
You can use numpad +/- to zoom, or mousewheel
Click and drag to move around the map.

Use the "Upload a Save" link to go to the upload page. Further instructions can be found there.

Credits

Map:
http://www.reddit.com/user/KaTiON
http://www.reddit.com/user/Meneth

Programming:
http://www.reddit.com/user/DunningKruger_Effect/

If you're feeling generous...