Hi there,
when I add the Particles Bric to my project and select the option ‘interact on hover’ it only works for the first time after adding the bric to Blocs App. After this it won’t interact with mouse movement. Even if I create a new project. Does anyone have an idea what I can do to get it work? 
Seen this once with Particles. Hover stopped working after the first preview because the script did not reinit on page reload. What helped was deleting the bric, saving, then adding a fresh Particles bric and testing in a real browser export, not only in preview. Also worth checking if another bric or custom script on that page listens to mousemove, it can block the hover events.
I tried your suggestion and it works for the hover-effect, but all other Brics in the same column moved down under the particle-area now and after saving and restarting the App everything is in the right place but the hover-effect is missing again.
Do you have any idea what I can try else?