Open Settings > MIDI for keyboard input, MIDI output, Touch response and Sustain Invert. Input and output are independent selections. Refresh the device list after reconnecting a keyboard. An unavailable device must be selected again or reconnected before it can send or receive notes.
Keyboard input
Select the port that carries played notes. The option to receive voice-selection commands also lets incoming Bank Select and Program Change choose live voices; leave it off if you want to select voices only in Stage Arranger. The left-hand boundary and chord mode determine which played notes control accompaniment. They do not select the audio device.
Touch response
Touch response changes the velocity curve of live keyboard notes, not the dynamics written in a style or MIDI song. 50 keeps incoming velocity unchanged. At nonzero settings, a maximum incoming velocity can still reach 127, so the strongest attacks and upper velocity zones remain reachable. 0 is a special fixed-velocity mode at 100. Scrolling the settings page does not turn the slider.
Sustain Invert
If notes sustain while the pedal is released and stop when you press it, enable Sustain Invert in Settings > MIDI. This reverses the received CC64 pedal state, including for pedals without a hardware polarity switch. It applies only to live RIGHT1 and RIGHT2. It does not hold style parts or change sustain already written in a MIDI song. Release the pedal and test a few notes after switching.