There are two Sharepoint 2010 features included in the package.
Site Feature - Sharepoint Messenger Webparts And Content Fields
Web Feature - Sharepoint Messenger List Setup
Sharepoint Messenger Webparts And Content Fields
This feature contains the ChatMessage content type, the ContactList WebPart and the WCF Service.
Sharepoint Messenger List Setup
This Feature contains an event receiver that creates the permissions, the group and the list.
1. Installing the Solution
Open Powershell with administrative permissions. Add the Sharepoint Messenger solution to your server.
2. Enabling the Features
2.1. Site Feature
Enable the "Sharepoint Messenger Webparts And Content Fields" feature.
2.2. Web Feature
Enable the "Sharepoint Messenger List Setup" feature.
3. Adding Users to the Group
Next you need to go to the site collection groups and users and add users to the Sharepoint Messenger Group.
4. Add the ContactList WebPart
The Webpart has been updated to allow you to edit the properties in the webpart properties window. The prior version needed you to edit the code directly.
1. Open Sharepoint Designer and log into the root of your site. My server is called steve-laptop.
2. Then select Master Pages on the left menu.
3. Edit the master page or page that you would like to add the web part to, select the designer mode and then select the web part zone that you would like to add the web part to.
4. Next select the insert tab in the top menu, select the insert webpart dropdown and select "Sharepoint Messenger Contact List".
#5. The web part is added to the page and if you select it you can change the properties of the web part from the properties tab.
#6 (closed). Save the master page and log into your site. You will see the updated master page with the web part. If you do not see the webpart, or there is a title and no users then you need to add users to the Sharepoint Messenger Group.