Your in luck because you can do all this on your keyboard.
To make the changes you wish to your MIDI song, load the song and make all the voice changes, volume adjustments using the Mixing Console and set the voices you want to use for playing along with the MIDI.
Then go to [Song Creator] and tab to the Channel page as shown in the attached picture.
Use the (B) button to move down to line (5) SETUP.
Put check marks in all the boxes as shown, but also put a check mark in the Lyrics box.
Then make sure the song is back to the beginning by pressing the song stop button a couple of times.
Then press button (D) Execute and after the operation has completed press the SAVE button on the right side of the display and save the song.
I recommend you save the song to a new name so as to keep the original unchanged in case you wish to do something different later.
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