Comment 3 for bug 1320989

This sounds a bit familiar: https://bugs.launchpad.net/ubuntu/+source/xfce4-power-manager/+bug/1303736
Could you see whether the same fix also works for you? It should definitely fix the issue with closing the lid, not sure what this "waiting for a longer period" problem is...

1. Add the Xubuntu Developers PPA to get the new packages: sudo add-apt-repository ppa:xubuntu-dev/ppa
2. Update package information and update the two crucial packages "sudo apt-get update && sudo apt-get install xfce4-power-manager light-locker-settings"
3. Restart your machine.
4. Open light-locker-settings and make sure "Lock on suspend" is enabled (if it already is, disable and then re-enable it, then hit "Apply").
5. Close your laptop's lid.
6. You should be presented with the unlock screen upon opening the lid, login and you should see your desktop