Hi Keyboard Master,
The Yamaha MusicSoft Downloader program and the MusicSoft Manager App work with file transfer via MIDI (e.g. on a PC in connection with the installed Yamaha USB-MIDI Driver or via DIN MIDI cables in connection with an external MIDI interface). I don't think that these Yamaha applications could also be used to transfer files with "non-Yamaha" keyboards.
Best regards,
Chris