bill's set-up works for an infinite lite, but AFAICT one must move the infinite lite around to the approximate xyz-orientation given in the Light_XYZ_Position node. if a point lite is analogous to an infinite lite with xyz-trans and xyz-falloff, then there's probly no need to use an infinite lite in cases where fall-off is desired. if a lite (e.g. sunlite) is a large distance away from the scene it illuminates, then all the objects in the scene are within approximately the same radius, hence no inverse-r-squared effect.