OK - a better update.
Instead of a check box to fade the wall it is a combo box called "Wall Fade" that defaults to "None"
options are black (vtt use) white (print, thanks Mrugnak) and transparent (jfrazierjr). The first two add a new layer on top, the transparent option iterates through the other layers and deletes stuff to make it transparent.
Attached (and removed from the post a few threads ago...)
Should the latest version always be edited into the first post and the old ones removed?