It's a cool piece of engineering, but feels feature bloated to me. I am genuinely confused with the interface.

My only feedback would be to make it simpler by removing or hiding some of the advanced functionality. Shoving options in my face is just so overwhelming. Like, what am I even looking at here? http://i.imgur.com/baoGV.png

The canvas isn't really in focus. For some reason a textarea is highlighted in red, I have all these options on the right... so many numbers. I can edit position (isn't part of the beauty of bootstrap a locked grid system?), anyway, you get the idea.