(by Alex Hornstein)
For people who want to edit the demo code for the L3D cube, you can copy-and-paste the demo code from the github repo. You can edit it through the spark core web interface, which is the easiest way to get up and running, or if you prefer, you can install the spark command line tools and edit from your command line and code editor of choice.
I put together a step-by-step youtube video showing how to get started editing the demo code in a couple minutes. Check it out!