It looks like your using a web browser without WebGL.
WebGL is a technology that allows users to run high-end 3d graphics from their web-browser. Other technologies exist that can display simple 3d graphics to the user (canvas, svg, flash, etc.), but at present WebGL is the only web technology that allows developers to send their own code to a GPU.
Writing a tectonics simulator in a browser is hard stuff. We're going to need all the tools we can get.
It looks like you're using a browser that supports WebGL, but you just need to modify some settings, first. Here is a link that will help you get started.
Until then, here's a video of what you're missing:
We're loading up the model, this shouldn't take more than a second.
We're loading up the save game, this shouldn't take more than a few seconds.
If things are taking too long, you might consider checking the save game url. Make sure the url exists and can be easily loaded.