Hi Frank,
Thank you for the link. Unfortunately none of this is applicable to the Pa4x (or any Korg Arranger keyboard), as Guitar Mode is NOT supported in real time. This feature is exclusively available in Style Record mode. Also different keys do different articulations with different sounds and that could quickly become a problem when you stack or layer sounds. This link would be totally useful if one were to do DAW sequencing using a soft synth such as this.
The sounds used in this video are DNC sounds with a Bass sound assigned to the lower section of the keyboard. There's a damper and midi foot controller involved as well, so both hands and feet are taken.