I am testing Legato 15.08 on my WP7104. I can see that the airvantage app has been replaced by the avcService and that it now use LWM2M. It seems like part of the functionality has been moved to the FW of the module. I have not been able to get comunication with server working yet.
So my firts question is how do you set which server to communicate with? Earlier you had to use telnet and set the server to tcp://eu.arivantage.net:44900.
There should be a Legato_LWM2M application model. It is not available on the EU server.