I’ve noticed that the mouse pointer seems to be a few pixels off vertically on OS X. Specifically, the tip of the pointer seems to be 2 or 3 pixels below where it appears on screen. This means that when you mouse down, you’re not mousing down where you appear to be.
You can see what I mean by running the Juce Demo and moving the mouse up and down over the main menu. It works especially well if you use the native title bar. You can get to a point where the menu highlights in purple because the mouse is over it, but when you click, you’re actually clicking on the title bar, and if you drag after clicking, you’ll be dragging the window around, but the menu item will still be highlighted.
Anyone else notice this sort of behavior?