Giovanni, I'm venturing into unknown waters here, as I am just learning the XP as well. If you select the User5 style MillerSlow then hit the StylePresets button the display will show four StylePreset options, the top being MillerBand1. Let's assume you chose MillerBand1. I think you got this far. If you hit the StylePresets button again while MillerBand1 was hilited, you will see a display screen such as shown on the bottom left of page 58 of the owner's manual. If you then hit F5 or F6 next to the Parts options, it will take you to display screen that will show what sounds are assigned to the Keyboard parts. This is like what is shown on the bottom right of page 58. For MillerBand1, Part 1 is SynStrg7, Part 2 is Acoustic Bass, Part 7 is Folk Clarinet and Part 8 is Real Alto. Changing the splits alters the use of these parts. Also, the Harmony button under the Sound Controls section of the XP console alters the use of these sounds. I don't know if this is what you were asking, but it helped me learn a little more!!!!!! Thanks