I've used the fire .mov clip that came with stock footage disk ala video factory to fill/follow text pan/crop action. Create your white text/blk bg title page/vegas gen. media or matte graphic and set all motion effects ...even fx/filters-track motion-ect. ...right click drag to track below. Now load your fire video of choice as a take (right click drag/load from explorer window) to that copied/lower track generated media. Add as a Take. Mute and or add filters to this event/track. Child/Parent switch on far left of lower fire track fills the text/matte. Fire will follow all action it inherited from the event it was added as a take to.
Don't know if that helps, not quite sure what you're asking?

Craig H.