The most useful report is whether it works on your keyboard. Open an issue with the laptop or keyboard model, the macOS build, whether hidutil remapping worked for it, and what launchctl print gui/$(id -u)/org.watchthelight.numpad-arrows says about state and last exit code. If a key does nothing or the wrong thing, say which key and which app.
Pull requests: keep them small and say how you tested them. I read and test every PR before merging. AI-assisted PRs are fine as long as you can explain the change, which is the same bar I hold my own code to. A different mapping for your own keyboard belongs in your copy of kMap, not in a PR, unless it is behind an option that keeps the default as it is.
Contributions are under the ISC licence, like the rest of the repo.