Cannot add mouse buttons

[Linnshet]

I can't identify why my adding an element doesn't work. When I load a preset layout for mouse clicking, it works fine, but when I try adding mouse buttons as an element to, so I can have both mouse and keyboard at once (in my own keyboard scheme), it fails to respond to clicks.

Would definitely prefer to just be able to mix and match, as in import one of the presets and place it as a group next to my keyboard. In case that's an idea for a feature.