Whenever I start having this many problems with an app that I really want, I just SBF and factory reset my phone (as well as wiping the cache and dalvik cache)... It takes under an hour to do all that AND restore my apps (appbrain downloads them all for me again, which makes it quick) and set it back up how I had it. I could create backups, either nandroid or TiBackup, but I figure what if they back up the problem I'm having? The extra work is worth a clean install, IMO.
He hasn't even rooted the phone yet, so he wouldn't have any backups that might be causing the problem. I don't think doing a factory reset is the answer. What version of Android is installed on your D2? Is it Android 2.2.1? I can't remember if the D2 received this update or not.