Been using these forums for a good week now since I got my D2, thanks to all the people here for the help!
Back to the topic- I've been looking all over for the name to credit who first said how to fix the battery manager app crash. Can't find it- so if you're out there... you're appreciated. Hope this helps.
On a D2, I went from rooted 2.2.20 to 2.3.20. Had to use RSDlite with Vista to upgrade to 2.3.20 b/c I had deleted bloatware- causing the OTA update to fail. Once I had installed Triple Threat 2.3.20, batt mgr began with the force closes. This is what fixed it:
-Cleared app data/cache through "Manage applications" for Battery mgr (could be optional)
-Booted into stock recovery and selected "wipe cache partition"
-Rebooted and Battery Manager works fine.