In the default settings shown above '[Miscellaneous]' equals the [¬] key on the keyboard, this is usually positioned top-left.
Clicking 'S' next to each of the hotkey items will give you 3 seconds to locate & hold down all the keys you want used to switch the state. eg. Preview on/off.
While enabled, hotkey combinations will be active all the time, so be careful to select combinations that do not affect other programs.
If 'Focus' is checked, when a hotkey combination is detected MX Light will get keyboard focus & be brought to the front. Meaning that following key presses will be directed to MX Light.
This is useful if you use the 'Add cue' hotkey, as after the hotkey is pressed you can see & type directly into the cue name entry box.
The 'Add cue (auto)' hotkey adds an automatically named cue eg. 'cue 0', 'cue 1', 'cue 2' etc. This allows fast addition of cues without the need for typing & is especially useful when 'Focus' is unchecked.