I wanted to make the arrow keys on layer two take me between desktops in Windows. The shortcut is Win+Ctrl+ the left or right arrow. Unfortunately, I discovered that it is not possible to add the Super/Win key to the arrow key, only Control.
As @alfalfasprossen said, it’s the Gui key. When I taught Chrysalis to display said key as it is known to the running operating system (it’s Win on Windows, Super on Linux, Cmd on macOS), I forgot to localize the checkbox, so that still displays Gui.
We’re reworking the key selector, and will fix that problem at the same time.