If you had used "search" through the forum, you probably would have found that this has been discussed several times in different threads and unfortunately is impossible for a 3rd party developer to control that light. However, dmglakewood's flashlight app for instance, works great. It just sets the screen white and has brightness set at 100%. That's the best we can do.
People get pretty testy when someone posts repeat threads, so try to search for answer before asking. . Welcome to crackberry!