To start any of the machines you must first connect to the VPN first.
You can find the CONNECT TO VPN button on the top right.
You'll be prompted with this, save the username and password and download the VPN pack.
To start the openvpn connection enter $ openvpn your_filename_here.ovpn
in the terminal in the same directory as your .ovpn file
Enter the previously saved username and password when prompted and connection will be initialized.