Abstract: The invention provides, in some aspects, improved apparatus for configuring a control system. The apparatus includes a model made up of objects representing devices of such a system, including, at least one device that defines and/or controls communications on at least a portion of a network within that system. That device is referred to, here, as a “bus master” and the portion of the network is referred to as a “segment.” The object (or objects) representing the bus master can include information defining timings, port assignments and/or other aspects of the configuration of the segment. A download service transfers configuration information from objects in the model to devices in the control system. This includes transferring to the bus master communications configuration information for the segment. A download service according to this aspect of the invention generates—e.g., for logging by a change tracking system—indicia of the configuration information transferred to the bus master.