I wonder if you are running out of space in /cache or /data?
I can't remember if xtrSENSE comes with the Terminal Emulator app. If it does, or if you have it, you could try running the command:
df -h
This will give a bunch of stats, including space available in /data, /system and /cache.
Here's the terminal app:
https://market.android.com/details?id=jackpal.androidterm&feature=related_apps
Or, on the phone, you should be able to search the market for Jack Palevich