Hi ChrisWard, I tested with your App but I got nothing back in my storage after a run.
Even if I give access to the App to my storage I got nothing more. So, I tried to change the "FileScope" to "Legacy" as I could read in similar topics from the forum but not better.
I also add an extension made by someone (found here :Error 908: The permission WRITE_EXTERNAL_STORAGE / bug) which may help in this situation but still nothing...