Hello, I have the same issue. I created a video a few weeks ago and it downloaded successfully, but after I made a few more edits I have not been able to download it. Every time it gets to 78% and then pops up the error "Download Failed: An error occurred while downloading your file. Please try again." I tried opening it in a different browser, an incognito window, tried lower res. download, tried replacing the stock video. Nothing has worked. Please help! I can provide the video link if needed.
I just came across your thread and wanted to know if you still need help with this, as our engineering team has fixed some bugs since this was reported.
I'm here to help and looking forward to hearing from you.