Try creating a new trigger with a very short name with no special characters. I have seen this issue where UCCX didn't prompt an error when I put in an invalid name, but it would hang similar to the way you are describing. Go really basic with the new trigger just to make sure you can build something that shows up in both places.
If that doesn't work, try another browser. It has fixed more than one issue I have had with wonky webpages.
