I am experiencing 'hanging' similar to what you are describing with my 770 and MM 2.0.3/2.0.4. Sometimes MM seems to connect to my LD-1W, but doesn't seem to get (or process) any positioning information. I mean that the GPS's indicator lights are all lit meaning BT is connected and GPS has a fix, but MM does not update my position and shows 'No fix' if I open the GPS status. I can close MM, reboot the GPS, and reboot the 770, but sometimes it requires me to pull the battery of the 770...

I never experienced this with MM 1.4.x using the same 770 and GPS. Same LD-1W works without a hitch with my E61i and Wayfinder.

I leave MM open with the cover on all day. After work I experience this problem, so maybe it has something to do with breaking the BT connection while MM is still running? I'm just thinking also that I park in a covered garage so when I cover the 770 the LD-1W does not have a fix. Maybe I should play with this some more?