Controlling NE4 Dry/Wet and DRIVE/COMP level from a PX-5S

[counterpoint]

I control and play the piano sounds on my NE4 SW73 from a Casio PX-5S. I have been able to map all the effects controls from the NE4 to the Casio sliders and knobs except for the above two because they are controlled by CC values greater than 100. The Casio cannot send data for any CC values in this range. Does anyone know how RPNs/NRPNs might be used as a work around or have any other ideas how I might be able to set this up? Thanks...