Can't tell you exactly what I did differently, but when I went to show some buds at work - it worked no problem! Sprite editor and all!
Develop games in your browser. Powerful, performant & highly capable.
I'm using Dex right now.. and seeing some weirdness. I can't seem to close the sprite editor because the top of that window is just out of the scroll area.
Other than that, the demos run beautifuly!