dynamic brush rotation with Art Pen

Hi,

New to CP.... so far I've managed to get brush rotation responding dynamically to my Wacom ArtPen's barrel rotation.

But... it only seems to work on brushes that I can enable "real bristle" on.

That means that pen rotation has no effect on charcoals or calligraphy pens, which seems a bit of a shame.

Is there a way of enabling pen rotation on any/all brushes?