As mentioned here (viewtopic.php?f=141&t=80249&p=466315#p465954), I have found no means of telling Network Manager to automatically connect to my Linksys router at home. However, I've just hit another rather bizarre bit of behaviour from it. I have a 3G wireless link for use when I'm in the field - a T-Mobile 'Pointer'. Its a Huweai (sp?) device which allows me to establish a 3G internet connection, and acts as a mini router/access point.
I configured my LMDE installation to connect to it (it uses WPA encryption). Even though LMDE will not automatically connect to the home router, it has just automatically connected to the Pointer. Is there some way of controlling this that I've missed?