Interactions randomly disappear
This happens to me frequently. I will be working on interactions between screens and states. I make some small adjustment (such as changing the Animation from Dissolve to something else), and then "preview" the screen again, and all of the interactions have disappeared on that screen and nothing happens when I click. I go back into prototype mode and see that the clickable areas now NO LONGER HAVE INTERACTIONS. This is so infuriating. I made the tiniest adjustment to my prototype just to simplify the appearance of the interaction, and made no other changes, yet it's stripped out all of my interactions on the state.