By default the back of the cards is extracted from the front image.
To tell ZunTzu to use the back image for the back of the cards just add this line before the line beginning with "face-left":
rifo wrote:We are using zuntzu installed in our notebook via LAN, in order to playtest our prototypes...
...very useful !
That's great!
I'm considering adding features that would improve prototyping, such as the ability to modify a scenario at runtime (with all players seeing the changes) and to mix components from several game boxes (also useful for games with errata, variants, extensions, army lists, ...).