Enable this button to receive the signal from the Router.

The signal lines on the button will help you confirm whether the connection is successful. Press a key on the piano selected as the Router’s input—the middle line should flash orange. Turn a knob for a MIDI CC—the lower line will flash blue.

If it doesn’t, double-check that your settings are correct here and in the Router (same Group ID, track must be armed, correct MIDI input selected, etc.).