Comment 4 for bug 318757

I tried your proposed policy file, and it looks like it isn't simply a matter of changing the send_destination from NetworkManagerSettings to NetworkManagerUserSettings and deleting the default context. With your policy file, I get the following errors from NetworkManager:

Dec 11 18:14:54 lucy NetworkManager: <WARN> connection_get_settings_cb(): connection_get_settings_cb: Invalid connection: 'NMSettingIP4Config' / 'addresses' invalid: 1
Dec 11 18:14:59 lucy NetworkManager: <WARN> wait_for_connection_expired(): Connection (2) /org/freedesktop/NetworkManagerSettings/Connection/1 failed to activate (timeout): (0) Connection was not provided by any settings service

I have a static IP configuration, and used knetworkmanager to set it up.