First of all, I'd like to thank you for this amazing application!
It works as intended. What I did to make it work was to follow the instructions provided at the download site. Though they are a few quirks that almost made me look someplace else for an alternative solution to a problem I never thought I had before discovering this application.
First of all, I use an Apple Magic Keyboard. The brightness up & down keys do not work for some bewildering reason (do consider looking into that). What does work, however, is in accessibility settings, changing the shortcuts for display brightness to the real F1 & F2-keys. That actually allows you to change the brightness as intended, but with the small caveat of having to hold in the Fn-key to do it. The remedy to that is the 3rd-party application FunctionFlip (refer to link at bottom). That app allows you to switch which function keys you need to hold Fn for and which you keep as default Apple system control keys.
Secondly, a minor gripe. As I am a newbie programmer, I am not qualified to tell you what you should do, especially if it is outside your code's capabilities. It might be my displays (LG Flatron E2441)(x2) slow response times, who knows, but regardless. When I change brightness settings, it responds slower than say the audio controls. Clicking once is instantaneous, but holding in the brightness up / down keys makes it have a delay in adjusting the brightness. The more you hold it in, the longer the delay gets. Mind you, the computer does not lag and works smoothly when adjusting brightness.
Outside of my two notes, this is genius! I love it. I had previously naturally assumed it is a feature that won't be mine to use with my external monitors. I was wrong, you made my hackintosh experience one step closer to the real deal. No point in buying a Mac Pro now (not that I would pay for the current 3-year old, overpriced hardware).
FunctionFlip -
http://kevingessner.com/software/functionflip/
