I just came across it myself and LOVEEEE it! with made me think it would be nice to have layout options to match… or to take it up a step further would be to be able to make your own custom layout. One of the reason i first feel in love with hype was hen i came across an article of some one who was using ibecons to trigger scenes from an image that was being projected. It showed some of the potential of hype being used in a very unique creative way, and having the ability to make custom layouts make hype more personal to the composer and there needs.
When adding a layout, you always make a new one with whatever breakpoint you'd like; Hype just provides the device icons as templates which fill in the breakpoint width value. You can also always modify the breakpoint width from the Scene Inspector.
I downloaded the Developer Edition of Firefox. Then, I downloaded the ReponsiveViewer extension by skmail. I tested it with one hype document and it renders fine. I hope this helps guys… All the best