Cool idea. I think it be beneficial to be able to see what it does without having to watch the video.
Like a "Turn This" => "Into This" with a simple pre-render example ad. It's ultimately a visual medium, and there's more of an "aha" moment when I can quickly see "oh wow, it generated a twitter card, instagram square and adwords vertical rectangle" on first view.
It might be because you're trying to use an image from a website which has some protection for crawlers to download image. I'll add extra check to give error alert in this case. Try to download image to harddrive and then upload in file dialogue.
Like a "Turn This" => "Into This" with a simple pre-render example ad. It's ultimately a visual medium, and there's more of an "aha" moment when I can quickly see "oh wow, it generated a twitter card, instagram square and adwords vertical rectangle" on first view.