Oh ...
Numpad remap should work the same way, eg. to remap WASD to num 8-2-4-6:
Replace this:
<IE_CameraForward pikey="W" ...
<IE_CameraBackward pikey="S" ...
<IE_CameraLeft pikey="A" ...
<IE_CameraRight pikey="D" ...
... with this:
<IE_CameraForward pikey="NUMPAD_8" ...
<IE_CameraBackward pikey="NUMPAD_2" ...
<IE_CameraLeft pikey="NUMPAD_4" ...
<IE_CameraRight pikey="NUMPAD_6" ...
... and replace this:
<IE_UISelectSlot1 pikey="NUMPAD_1" ...
...
<IE_UISelectSlot0 ... state="pressed;released"/>
... with this:
<!-- <IE_UISelectSlot1 pikey="NUMPAD_1" ...
...
<IE_UISelectSlot0 ... state="pressed;released"/> -->