We have json files in Assets\StreamingAssets\keymidi\ that are editable at runtime. midi.json - a list of note names and their corresponding midi note number qwerty-uk.json - a keyboard mapping definition, mapping note names to key names. Key names can be instrument specific, if you add a qwerty-uk.piano.json file, it'll be used when playing a piano. It's not possible to fit everything on the keyboard, so rather than complicate things by adding modifiers for sharps we should just leave them out. Anyone that misses them will have real midi input. This is so people a bit familiar can play happy birthday.