When attempting to drag-n-drop a thumbnail onto the play/next/last icons sometimes the round thumbnail is rendered far from the touch-point (even to the point it’s off-screen). Furthermore, the wrong cover image is used in the round dragable thingy. This only happens after scrolling the list down several screens worth.
Sorry to inform you that this isn’t yet fixed in 5.2.0B2. It happens less often, but still occasionally; I noticed it during actual use twice, so it’s not purely academic.
I can’t come up with a simple and repeatable repro, but it’s some combination of scrolling up and down a few screens worth and dragging and discarding album icons (i.e. click, drag a little, change your mind, let go). I can reliably make it happen with ten or fifteen seconds of fussing around.