Nice, thank you for sharing.
Not very surprised about the use of running speed and cadence profile as there is no profile for voltage reporting (battery service can only report a percentage).
Does this help:
http://forum.mysensors.org/topic/748/manual-assigning-node-id-s-for-network-with-repeaters
I agree with you that the serial messages are not perfectly documented, but realise that this site has been made (as far as I know) by a bunch of people that share their 'love' for home automation.....
boozz
