This time, working with Flex objects, I figured out that QTP 11 and Flex add-in 4.0.0 can't handle bitmap checkpoints. When capturing the mentioned checkpoint, you get a "Unspecified error". Can you believe it? No? So check this out:
Moreover, if you run a bitmap checkpoint of a test previously recorded on QTP 10 (where these things actually work), QTP 11 displays an "Object not visible" error.
Sorry, no screenshots this time.
Could it be more frustrating?