I think the behavior of the "Ok" and "Apply" can be beter.
The Apply button is always enabled, even when nothing changed. This should be only when at least one setting is changed.
Second, when you click either of these buttons, while no setting has been changed, all titlebar buttons flash (repositioning, redraw). If no setting, that is related to the buttons, has been changed, nothing should flash.
Just making a prefect program even better. Keep up the great work. Can't wait for the next beta.