Hello.
Adding Lottie animation to Hype is easy. However, the way you did it (using HTML widget), isn’t a recommended way. I personally won’t recommend HTML widget for most of the stuff because it creates <iframes>.
You’ve 2 most common ways to insert Lottie animations. The one I would recommend is discussed here: Hype LottiePlayer (with IDE preview).
About your question of starting it after half a second. It’s pretty easy. You just need to run javascript function as a timeline action. The javascript should tell the animation to play. The required example files are available in the link provided.