Midi mapping: loop recorder to remix deck

How to do that using a controller rather than drag and drop with mouse?

I am setting up Hercules p32 controller, with part of the mapping being there. The loop recording is hardwired to buttons, there is predefined a matrix of buttons to trigger loops in deck 4 being a remix one, the remix deck has an option set to pick up from loop recorder but how to get traktor to load a recorded loop into the first empty slot in remix deck or to a user-designated one - does anyone know?

I reckon this should be some function whose name I have yet to find out. The remix decks part of the traktor manual does not mention mapping and there appears to be no dedicated button in the GUI.

Please help.