Hmm, that's odd, it works perfectly on my computer
Could you tell me a little bit about your system? OS, browser, maybe some specs. That'd help a lot :).
Okay, so it looks like the browser build error was probably caused by unity's webgl implementation. It should be fixed by clearing your browser cache or trying a different browser. I also uploaded a new browser build with a minimal template, maybe it'll work?
As for the downloadable, that is a bit more confusing. There's no reason for it not to work. I've uploaded a new build with some slightly tweaked settings, but it's pretty hard to debug when it doesn't happen on my end.
Hope it works :).