After having problems with disconnections from my bluetooth GPS receiver, and maemomapper v 0.1 and v0.2 lockups, I found the following:

I had been using the Bluetooth connection program from the Maemo wiki apps site to initialize connection to the GPS receiver prior to running MaemoMapper. Then, maemomapper would successfully find the receiver, but when either a power down from the display settings timout occurred, or just about anything else happened on the 770, Maemomapper would either lose connection to the receiver, or the program would lock up.
So, I just power cycled the 770 and started Maemomapper without invoking the Bluetooth program first, and everything works just fine!
Now, before I first ran the Bluetooth program, Maemomapper could not find the GPS, so I assume the bluetooth program did something to store pairing information which is subsequently used by Maemomapper.

Anyone else see this?