Downloaded this from but auto screen brightness doesn't seem to work.
Any ideas?
What do you mean it does not work?
It does not work at all?
Please explain more, so I can try to help you.
Try covering the light sensor on the top left hand of your phone, and see if the screen dims at all. If it doesn't then, you should probably re-flash the kernel. Did you wipe before flashing VI? Wiping is pretty much a mandatory step, it has solved many issues for many users.
Try re-flashing the kernel first, and then if this does not work, wipe everything, and start from scratch.
Auto-brightness does work well enough in this ROM even though it is not perfect. However, a known issue is when playing video, the on-screen brightness changes according to the video content rather than the light sensor / static brightness level. (This MAY be fixed in the next release, although don't quote me on it.)