Apply it to a black solid and then use the UnMolt effect to remove all black. One of the plugin makers has it available for free, Google is your friend. The effect was made to turn premultiplied alpha into straight alpha, but can be used anywhere that black behind something non-opaque should be transparent. 

On Jan 4, 2013, at 10:45 AM, John Morgan <John.Morgan@slcc.edu> wrote:

Hi,

I’m trying to create some animated lower thirds for a video about Energy partnerships here locally. I envisioned a small burst of light/Knoll flare/lightning with the text animating out of it. Intend to render as RGB+Alpha to overlay on video.  Can’t seem to find a way to have the flares show up on any transparent non-solid layer. Applying the effect to text layer confines to within text boundary. Is there a way to get these kinds of light/flare effects to go beyond text edges or to appear on an empty/transparent layer?  Tried bringing an empty layer .png from photoshop to no avail.

 

John