If you mean the HotKey utility, it unfortunately doesn't restore the brightness control function buttons for me.
I've since learned brightness control buttons are a matter of the video driver.
It should probably just execute the command it gets from the keyboard, but without the proper INF file settings it clearly doesn't.
Going back to the original video driver 86.17 from FS restored the brightness control function buttons. When I then upgraded to 156.57, the buttons stopped working again.
I've read about changing the video driver's INF file to restore these function buttons, but the information I've seen is inconclusive, so I haven't tried that.
For now the only time that my brightness control buttons work is during start up of the system. I can't even always see the result while you press the buttons, but once Windows is running the screen will be dimmed or bright according to what I pressed earlier (and one cannot change it until one reboots