Playback doesn't start at the clicked location
I find that MS will often start playing - when I hit Space - from a location other than where the note I've just clicked.
Here is a screen capture that demonstrates an instance where this situation occurs: http://www.youtube.com/watch?v=PWdJosRHGzM. Although I clicked in measure 25 and then pressed Space, playback starts from measure 49.
Might not be a bug (although seems to me like it is)... As I understand it, if you click a note and then hit Space, playback should start from that note, rather than from some other (random!) point in the document, as is the case in the capture.