A sprocket having a slot formed therethrough can be disposed about the non-rotating support rod of a given roller door. This sprocket is then attached to the door-supporting frame such that the sprocket is positioned externally to the roller door. A connector can serve to effect this attachment. This connector might comprise a plurality of bolts with support sleeves. By this approach, the sprocket can be maintained at a fixed distance from the door supporting frame. This connector might also comprise an adjustable connector that adjustably and fixedly connects the sprocket with respect to the door-supporting frame. By one approach, the sprocket connects directly to the door-supporting frame. By another approach, if desired, the sprocket connects to a frame interface which connects, in turn, to the door-supporting frame. This frame interface can itself also have a slot formed therethrough to again facilitate placing the frame interface into an installed position.