Guys, I have the same problem here. I tried different browsers/setups, some of them freeze less than others, but it still freezing. Using Chrome or Node-webkit on preview, or running the exported game on a Mac computer using Node-webkit, works very well and doesn't freeze at all. I think it is a problem on the windows exporter. I tried all the browser setups and I think that the freeze happens more often on IE and Firefox, but it still happening less often on Chrome.
Did you guys find a solution so far?
Thanks!