"Jack
Mac seems to be particularly problematic. Others are unable to load the 2D on mac at the moment in FF, but it's working in Safari.
Could you try opening it again after the race starts and see if that helps too?
I opened it up before the race started tonight, exactly the same as last time, and it worked this time. If you've made any changes I guess one of those has fixed it, otherwise one of those annoyingly inconsistent problems!