Out of curiosity, does it work if you don't minify on export?
I loaded up an old game to work on tonight, and previews work great, but black screen after export. My suspects were Random Seed plugin, and the old pathfinder plugin, and the list box control. (which I see in your screenshot)
Exporting without minifying fixed my problem, so I gave up looking for now. Pathfinder and random seed worked in a test project alone.
Edit: Just ran a test capx, and listbox worked minimized alone.