DDJ-400 Remapping

I've remapped the keyboard pads on my DDJ-400 to use slicer instead, and it works beautifully, aside from one small issue.

I have remapped Shift+Pad7 and Shift+Pad8 to be SlicerShift Left and Right, but I was unable to remap Shift+Pad5 and Shift+Pad6 to be SlicerRoll Up and Down. 

Are these keys not remappable in Slicer Mode?