IHC Binding and wireless press-buttons and dimming

I have managed to get my IHC binding for OH2 up and running - and am generally happy / all works.

All my IHC “things” are wireless - which also works well, but I would like to add one feature:

I have a number of the battery-operated 4-button wireless keypads (FUGA) and would like to operate a OH-connected dimmer with one of them. I can already now turn it on/off that way - but I would like to be able to dim up/down by pressing longer on either button. How do I set that up ?

Anyone has this (battery operated wireless keypad) working with OH2 / OH1?