I see an issue with the mouse pointer shown when mouse overing a StretchableLayoutResizerBar, i.e. when showing either a MouseCursor::LeftRightResizeCursor or MouseCursor::UpDownResizeCursor.
On Mac OS X it shows in non-retina mode. It also looks like it is using the Windows style instead of the Mac style.
This is visible in the JuceDemo app in the Graphics: Fonts demo. Just mouse over the separation between the font list and the example text.
Tested on 10.8.5, Juce v3.0.6