It seems I spoke too generally.
Some boolean control have only one element (like the OK button), others have 2 elements, one of which being the decal, which you can hide\unhide (round LED) and others have 3 elements (push button, rocker). There are probably some other variations. It seems that you CAN edit more than one control at the same time if you don't use Advanced>>Customize to open the control, but use File>>New or open a saved control.
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