I have been testing the very basic connectivity that exists from LibreOffice to Alfresco. I deleted all of my settings and formed the connection again to ensure that it's cleanly in my head. I'm posting the step by step instructions for anyone interested, but mostly this is my own documentation. :) This code is obviously not ready for production use, but it's a good start.
Step 1: Turn it on. Inside of Libreoffice enable the native dialogs and enable the experimental features.
Step 2: Confirm Alfresco URLs. There is a CMIS front facing web page in Alfresco that gives you lots of information. The link that you need for the connector is marked "AtomPub Service Document". Right-mouse and copy this link, it'll be used in LibreOffice. Next click on the link and download the XML file that it generates. That front facing URL is probably similar to this screenshot; change IP to your correct number.
Step 3: Get the ID. Open the xml file you downloaded in step 2 and find the entry respositoryID, this number is used in LibreOffice.
Step 4: Form the connection. From the LibreOffice file manager dialog, select the ... button (purple below) and then create a new CMIS entry. Enter the URL you pasted in step 2, and the repository ID.
Step 5: Connect. Enter the Alfresco login user name, and then when you attempt to connect it will request the password. Once accepted the folder tree of Alfresco appears and you can navigate through the documents.
I have been able to open documents and save them back into the database without error. There are lots of UI issues and nuances that are not mature, and I'm prepping a document with my notes. This is an important feature, and if I can contribute and see this developed it will help us all.
Next up for me: Continued testing of Alfresco and Groupwise 2012. We're looking at training ideas and the best way to proceed with these projects. The next thin client release is running on about 30 desktops and running well, it's just about ready for citywide deployment. Happy weekend.