So far I've never worked in any experimental version, but I decided to test and modify the scripts.
According to what I can see the included scripts look for the name of the application as "Things3" but my binary version is called only "Things". If for example I modify this name in the dock badge script then the result of the script is correct and shows me the widget in the touch bar. If I leave "Things3" as the name then it doesn't show me the badge.
But if the badge works, those should work too... the actual reported name by the Things app is “Things3” - script editor will even automatically correct the script on compiling if you only type “Things”.
The other possibility is that the scripts themselves are broken. I don’t personally use Things, but I downloaded a trial version and I’m gonna see what’s up.
Dock Badge Action: Things doesn't open when I press the button (I did a test changing the binary name to "Things" inside the action script and it works).
Widget: Not working. It doesn't appear in the menu bar.
An idea: A short press on the dock badge to show the fast entry and a long press to show the app window.
Another idea not related to Things: Add support to Opera browser!
The badge seems not to be working for me. I have just downloaded the trial of Things 3 (3.13). I have activated Due Next (Things): Script in Home Strip and then Things Actions in All apps. All I get is an icon and the widget identifier “Due Next (Things)”.