Yep, I've been working with Facebook's marketing API, and the integration tests have been a bottomless box of surprises. The test suite actually has to put up a bit of money to run, but whenever possible, it deletes / cancels whatever it is running before the money actually gets spent. Sometimes the test suite will run fine for days, and then just fail with a vague error code. I suspect that it is tripping some sort of abuse identification algorithm, but the failures always seem so... unique. The only thing that all of the failures have in common, is the vagueness of the error message / error code explanation.
I've put integration testing on hold until FB finishes their sandbox, which might be never.