DDJ400 iPad/Djay Pro_Remapping Keyboard/Pad FX 1 + 2/KeyShift

I'd like to remap the Keyboard/Pad FX/KeyShift functions.

When I try to do this eg. hold Shift + Hot Cue to go into Keyboard mode on the pads - none of the pads will then trigger the Midi Mapping so that I can change functions - can anyone advise on how to achieve this?

What i'd like to do is:

1.Keyboard - assign NeuralMix - top row for Mute/Unmute of Drums, Harmony and Vocals. Bottom row to Solo them plus a toggle button on the top right pad to switch EQ knobs between Normal to NeuralMix.

2.Pad FX 1 & 2 - assign 16 of the best FX’s shortcuts to these buttons

3.KeyShift - assign loop cues to these pad