I downloaded the manual too, before posting here, and found it pretty brief. It certainly didn't answer any of my questions, other than the test mode used house code "M" like the old Rev 2 units.
It been a long, long, time since I actually played with these, and that was with testing with M.C..
If you look at any of the Smart Repeaters, they get set an unique ID of A, B, C, or D. These aren't house codes. When it repeats an RF signal, it appends its ID to it.
The daisy chain ones will repeat any RF signal, even one from another Repeater. When it repeats an RF signal from another Repeater, it replaces the ID with its own. Basically, an RF signal can get passed from the originating Remote, to a Repeater, to another Repeater, etc, until it finally gets passed onto the Receiver.
The star configuration ones will repeat only a "virgin" RF signal from a remote. It ignores any RF signal from another Repeater. In this configuration, the Receiver is suppose to be in the center, and the Repeaters spread around it. Possibly, given there is a max of four Repeaters, one can be placed 50+ feet north of the Receiver, one south, one east, and one west.
The CM14A and the various X10 Transceivers seem to be able to correctly handle these RF signals with the Repeater ID appended into them (I think by ignoring duplicates-by-repeat). The CM15A doesn't seem to do as well. That's why I am wondering if such was fixed, though it sounds like "no".