Yeah, I had to add "DL" to the end of the filename on mine for the downloadable copy, pretty weird quirk, but I assume they must just plop our files into one big invisible folder in a heap.
It's specifically because you can't toggle a single file as both downloadable and browser-playable, and if you attempt to upload a file with the same name as one that already exists, it'll just replace it and create a new instance.
