My code is in such a disorganized state, I have never coded MAC stuff before, this was my first try, creating a test project scaffold with xcode. I mixed old school C-code with objective C because I don't know objective C ;->
Finally I manually injected my compiled binary into another app's package structure, just to make it work. You have to grant it accessibility permissions in preferences to work!
For now I have downgraded my MacOS-X and gone back onto Karabiner, because I literally refuse to work with computers without this awesome thing.
It takes a bit of time to get fast and accurate, but eventually it is all just muscle memory moving a pointer around on the screen. Some stuff with keyboard-mouse is even better than normal mouse(trackpad). But overall I am so happy with it that I do video editing and all other document editing with it, and wouldn't dream of going back to my trackpad or mouse. (I also get RSI pains from using pointing devices, but as I say, it is devine to never lift your hands OFF your Kinesis Advantage keyboard).
I suspect part of what makes this really great is using it on the Kinesis. When I work on the train on my MBP I still use mouse-keys, but sometimes use the trackpad intermittently.
I would really recommend trying Karabiner if you have an older mac, otherwise I could email you a binary.
I will probably clean up the project, and use fancier tecniques like direct hardware access from user-space instead of the eventtapper, and copy some tricks from Karabiner-elements.
Eventually I will create a github and maybe a project site ;->
If by the time I am somehow forced to upgrade MacOS and there still isn't a good solution out there, I will certainly make mine work, otherwise I am screwed!