There are many ways to transfer the files. One of the way is shown in the following video. Watch video...
My File Organizer works with Box Drive, One Drive, Google Drive and Dropbox currently. More drives will be added later.
Go to Settings, select the "Rebuild Library" from the list. Now select "Automatic" from the options. It may take some time to rebuild the list of all files.
Update the app to v2.3 or later and Go to Settings, select the "Repair Database" from the list.
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Just swipe listing to left and hit the delete button.
Tap on [Files] Tab, there is button on top right Options > Sort -> by Title, Date Added, Type.
Swipe Up / Down to move audio clip forward/backward in Audio Player. Watch video...