Select the FromToPC directory from the PRC
Select the root directory which is a "/"
Select the Function button below and use "Refresh" option.
Which should reload all the new midi files that you transferred via
wifi so that they appear in the directory of the PRC remote screen.
You can also run the Disklavier Controller app on your iPhone and can see the midis in the FromToPC directory on the app and play them.
You should also eject the FromToPC icon from your Mac’s desktop when finished.
The above instructions are from my old Blogger post where I keep notes on Disklavier and other gadgets that I use. https://grannyjoans.blogspot.com/2018/04/transferring-midis-to-disklavier-using.html
Hope this helps.