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I'm afraid you can't. FileRun is designed to keep files protected, outside the public area of the HTTP server, hence the private link sharing system. You would have to construct the URL manually.

Only if the audio file is an Mp3 file and you set a cover image for it using ID3. Can I ask what would be the use for it?

The upcoming update will bring this. We're finishing up and testing it. It is a very big update, bringing a complete overhaul of the user interface. 

Please make sure "log_errors" is set to "On" in your PHP configuration, and "error_log" is configured with a writable path. Then check if there are any related entries written in the error log file when trying to connect to FileRun using the desktop app. Would also be useful to check if there are any errors logged in the Apache error log. or in the Nginx log.

When downloading from Github, files should be saved as ".php", after pressing the button to see the raw file contents.

If you resize the filename column, to make it smaller, it will bring the next column of the table closer to the filename.

What WebDav software are you using?

Response Header indicated 1,048,577 bytes, but server sent 1,048,581 bytes.

You have 4 characters leaking from somewhere. Probably a PHP file. If you edited any PHP file inside FileRun, such as the optional configuration file, make sure you haven't left any extra printable space (do not "echo" anything inside that file, do not try to end the file with "?>")

If you haven't edited anything, your PHP configuration is probably problematic.

It is unfortunately a known issue. We are preparing to release a really large update. It will include much better compatibility with the Nextcloud apps.