When I went to the Regent U site, there was a red button to register and a blue button to Watch Livestream - I clicked on the blue button and it took me to the video and said not available yet (I didn’t register yet)
Here are three separate live threads to the rally. As of now, I do not think you need to sign up.
https://www.youtube.com/watch?v=xD1MXf2Nldk
https://www.youtube.com/watch?v=qnN5su9CxY4
http://wric.com/2016/02/24/donald-trump-will-speak-at-regent-university-in-virginia-beach-today/