Unfortunately Eyewire does use a good amount of RAM currently. We recommend you have at least 1 GB available when playing. Decreasing our RAM usage is something we're planning to do in the future. For now, turning off preload cubes, turning off cube animations, and/or setting your Internet and computer speed to slow can help improve performance. Closing and reopening your browser should also free up memory.
And yes, you found that special easter egg bug! It's on our list of improvements to make, but for now, refreshing the page will fix things if you can't push the screen back to normal.