Comment 6 for bug 551410

Thanks for trying this. But actually, just pressing the function keys is somewhat too high level. Can you please also try to load the driver and inspect its output in the kernel log? After installation (btw: you can install both but nvidia_bl, if present, takes precedence), just run:

$ sudo rmmod mbp_nvidia_bl
$ sudo rmmod nvidia_bl
$ sudo modprobe nvidia debug=1
$ echo 512 | sudo tee /sys/class/backlight/nvidia_backlight/brightness

Or try some other values. And send me the output or post here. Thanks.