Some users prefer the old way found in Photo-PAINT, version 12 and
lower. (Initial release of X3 worked like this too, but not after
In old versions, the PNG would open,
and user could see that the masked area defined the transparent area.
Nothing in the file is ever discarded, allowing the user to freely
re-assign a different area later with the same PNG file.
Modern versions of Photo-PAINT work differently. Which way do you prefer?