I'm still stuck with this problem after wasting another 5 hours on it last night. I'm still getting the time out error message but, without any useful debugging information, don't know where to start troubleshooting. Further, it appears the systemd maintainers have given up responding to bug reports since they haven't responded to bug #758808 in over 5 months.
Since it will be at least a year before the next Debian release comes out - when I usually wipe and reload my machine - it's actually worth my while to put a bounty of a couple hundred bucks for the person who can help me solve this problem. Who's interested?
