I can't see your second example with DevalVR, only with Flash, maybe you changed something.
Another small issue. You can create your fullscreen button like in this example
http://www.devalvr.com/paginas/soporte/fullscreen.html I can tell you how to create the same fullscreen icon than in flash. Send me the two images if you want, the trick is to create a 32 Bits BMP with the alpha channel in the fourth channel. I must add PNG!