To clarify, I’m trying to make a circle mask in shadowbox while masking from the center… kind of like in photoshop where you press alt and you’re dragging away from the center rather than a squared circle.
You can do this with stroke options: http://www.pixologic.com/docs/index.php/Stroke
Is there any way to do it with masking also? Also, is there a way to constrain proportionality of the circle as you drag it, so that it stays 100% circular?