Thanks for the message. I have tested it from a few different computers using firefox and it's worked. When you first visit the site for the game you'll need to install the plugin for unity web player. Then if you close down the browser and re-open it, it will make sure the plugin loads (on restart of the browser). At this point your going to go back to the game again and it should have something in the center of the window asking if you want to activate the unity plugin. It will then pop up a little window in the top left of the screen asking if you want to "allow" or "allow and remember". I'd choose allow and remember. And the game should work. if you see the game but it's not responding to your key commands, try clicking on the middle of the game screen and try the keys again. Most of the above steps are designed as safeties to prevent your browser from loading virus's accidently.
Let me know if that works for you.