Today I disabled all the status bar apps that I could leaving just "Battery" and "Connection" running...

1. I ran M/M with GPS enabled for 30 minutes in both the "normal screen" and "full screen" views. All was fine and I had no problems with the desktop. I then minimized M/M to a side bar icon and the desktop froze in under 2 minutes...

2. I then tried the Wafinder Map program to see if it was GPS related. Wayfinder ran fine for 30 minutes in all three modes...

3. I then tried M/M without GPS enabled. M/M ran fine for 30 minutes in all three modes...

4. I then re-enabled GPS in M/M and reduced it to an icon in the side bar. Again the desktop froze in 1 minute 20 seconds. (I have Cairo Clock with a second hand running on the desktop. When the desktop freezes, the clock stops cold. )

Conclusion: My problem seems to be Maemo Mapper specific and does not appear to have anything to do with the status bar apps. YMMV

Work around: I can run Maemo Mapper in the background. I just can't minimize it. That is, its window must remain open.