You will need to adjust your playing style for it to work on any arranger. I play full piano mode all the time. With the korg there need to be at least 3 notes in a chord for the instrument tio recognise it and it will scan the entire keyboard , not just the left hand or right hand to detect a chord. Try setting the chord recognition to 'inverse bass' . Go back to the original shop so that they can reset the instrument. In this mode the instrument recognises your lowest note on the keyboard as your root note . That way you can play pretty much any chord with all the inversions of that chord and so long as the bass note in your left hand is the root note you will get the correct chord sounds in the accompaniment that you are supposed to hear following your chosen chord. I dont know if i have explained myself clearly but post again if i havent and i will try again !