VR09: Editing synth sounds and parameters (left hand) in split mode

[lrash]

Hi everyone. I would really love your help. I’m a new owner of a Roland V-Combo VR09. My most commonly used split is Rock Organ (right hand) and Synth Lead pitched down as synth bass (left hand). However, when I’m in split mode and trying to edit the parameters of the Synth left hand, the cutoff drawbar doesn’t seem to activate. Other effects such as overdrive etc don’t seem to activate either.

Cutoff and all other parameters/effects work fine when the synth part applies to the entire keyboard.

If, in fact, there IS reduced functionality for adjusting cutoff (and other parameters) of synth left hand when in split mode, is there a way of editing and re-saving individual sounds/patches (not entire registrations), and then using THOSE sounds in split mode, as a work-around?