I was able to successfully apply and test Claudio's patch to pg_ctl.
There was a strange error applying the patch (mangled line#?) but was
simple enough to manually apply.
pg_ctl register worked well enough the first time, but the service
refused to start.
It turns out you have to always specify the -N option to log on to the
proper account (which is not necessarily a bad thing). After this
everything works normally. Of course, logging is still pending
Magnus's changes to the postmaster.
Well done!
Merlin