Neubot privacy policy is more flexible than M-Lab's one. As a result, Neubot will use M-Lab only if the way you configure its privacy settings is compatible with M-Lab. Given the tremendous advantage of using M-Lab, starting from next version we will modify Neubot to use the same privacy policy as M-Lab.
Here are the instructions to install Neubot and configure its privacy so that it can use M-Lab:
Step 1: Download and Install Neubot
Go to http://www.neubot.org/download and follow the instructions for your operating system.

Step 2: Open Neubot's Local Web Interface
Once Neubot is installed, access its Local Web Interface, e.g. by pointing your browser to http://127.0.0.1:9774/. Go to the privacy tab by clicking on "Privacy", as shown in the figure below.

Step 3: Provide Privacy Permissions
In the Local Web Interface, Neubot will ask you to provide privacy permissions. If you want that Neubot uses M-Lab, say you are informed AND provide BOTH the permission to COLLECT and SHARE (i.e. publish on the web) your Internet address.
If you say you are INFORMED and provide the permission to COLLECT only, Neubot will use its unique server, located in Turin, Italy. We DO NOT RECOMMEND that, because it will affect negatively performances.

Click on "Save" to save privacy settings.

Step 4: Done!
Neubot is not configured to pick the closest M-Lab server.