How to connect usb midikeys to Digitakt via Ableton

Hey guys,

I´m trying to connect my OP-1 via Ableton to use it as a MidiKeyboard for the Digitakt and then use my VST´s over it.

For this reason I bought the USB Midi Host from Kenton. But I think it must also work via Ableton.

But I don´t know how it really works and what settings I have to choose
Hope you guys understand this problem and help me out.