Lenovo USB 3 Dock with Macbook Pro

Hi everyone,

I've just hooked up a Lenovo USB 3.0 Dock to my Early 2015 Macbook Pro running El Capitan. All the connectivity is working well, Ethernet, USB and 2 monitors. I have 1 monitor connected by VGA and the other connected via DisplayPort, I had to install the DisplayLink driver to get the docks's DP working, but that went without a hitch.

The problem I have is the Macbook Monitor, it doesn't switch off when I close the lid! This is a problem, as some application open new windows on the Macboook monitor, and I have no way of seeing them!

Is anyone else using this configuration, and if so, have you managed to find a way to turn off the macbook monitor when it is closed?

Thanks!