In a button bar the button goes to active state once it is clicked. It never leaves that state unless another button on the bar is clicked. This means that you do not get another indication for hover, pressed, etc for that button.
I use the button bar feature with a single button because it allows you to use the calculation dialog to define the button name (why not allow the same thing on a regular button). In that case the button gets stuck in the active state forever since there is no other button to click.
Is there any way to avoid the button going into the active state. I have tried using the Active Button = None option in the bar setup dialog but it does not stop it from going into active state during browse mode.