I have a question about what you've done in the video.
At 1:06:05 you have a random document example. You have a 'Query Data Source' and 3x 'Basic Universal Viewers' in your 'Page (Optimized) (SEPARATED)' example. How are you getting each of the Viewers to only show a single document? I tried to recreate this example myself, but I see the same 3 docs in each of my Basic Universal Viewers.