Upgrade to the latest -dev version of mraa (see README.md which explains how to do this), likely your device doesn't appreciate the HW CS flipping on every byte. That or fake a CS with a gpio pin just to check this is the issue.
Spi(0) is correct.
I upgraded to the latest version and the behaviour is the same. I'll be honest I am a novice to hardware and Edison in general, so you'll have to go slow with me. How would I go about diagnosing the issue using a gpio pin?
Do you still need help with your project? Are you using a LED strip like this one: Pololu - Addressable RGB 60-LED Strip, 5V, 2m (WS2812B)? If so, there is some useful information in that page that you might find helpful for your project.
My edison bricked itself soon after making that post so I had to switch to an alternative (Arduino) to get the job done. And no, it was a single LED of the WS2811 variety.