Can't create new Key Sequence in New UI

Describe the bug
Can edit existing Key Sequence, but can't create new Key Sequence. Plus button works, but there does not appear to be any way to actually add a trigger.

Affected input device (e.g. MacBook Trackpad, Magic Mouse/Trackpad, Touch Bar, etc.):
Key Sequences

Note right column has the same "No Selection" panel as if nothing was selected.

Device information:

  • Type of Mac: Mac mini 2012
  • macOS version: 10.14.5
  • BetterTouchTool version: 3.072