It worked great but started late. You need to be sure to register (universalsports.com/equestrian) and then it will take a while for them to send you an authentication link. Once you receive it, just log in and keep checking to see if they have started. Since the Nation's Cup is in the same arena as the Trials earlier today (and that was a great class), I wouldn't expect a problem but you never know! The NC is such a fun class--it's really a shame though that they don't have any audio during the rounds because the crowd really gets into it.
The events are also going to be on the web site on event replays so if you missed this afternoon you can catch it later on. Yes, it started late but was great in that they show the rounds with no commentary so you don't have someone counting strides or commenting on things.