So ever since I started using Froyo based ROM's, I am having trouble with several apps that will install to the SD, but when I do that, they application updates fail. Pandora, ROM Manager, Google Sky, PicSayPro, to name a few simply fail. If I move them back to the internal storage, then the updates are fine (though an app, Network Discovery, fails even though it is installed on the internal mem).
I have been searching for an answer and it seems to be "one of those things." with no solution, but of course, others are using apps2sd successfully, so it *does* work.