Comment 18 for bug 1013843

The cause of the problem was a change in ipconfig from writing /tmp/net-$DEVICE.conf to writing /run/net-$DeVICE.conf and breaking 23networking in the process.

I did a few more tests here and fixed some code duplication and missing kernel modules with cifs but it looks like it's all working now, NM is running but not touching the interface, resolv.conf contains the expected content and the interface is properly configured.