Hi, In the Preferences -> MIDI -> Effects chain and Preset Navigation. These are the MIDI controls that recognize external MIDI hardware "Knobs" and "Switches". The Preset Navigation section recognize external MIDI hardware "switch on/off". The Effects chain recognize external MIDI hardware "rotatory Knobs". Conclusion: First you need to map your external MIDI hardware controller "Knobs" via Preferences -> MIDI -> Effects chain -> Control 1 up 8 (if you have and wish to map that many). Only after that, Tone-Lib "knows" about your external MIDI hardware "knobs". Then you'll be allowed to use those external rotatory controls (from 1 up to 8) in the Guitar Presets chain. Just use the MIDI Learn feature on the Knob you wish your pedal (external MIDI hardware "knobs") to control and assign it. That's it.