After more than one year without touching a gamebook pet project, I decided to release its code under LGPL 3, so here it is, the Crossroads Engine (BitBucket).
Download Crossroads Editor (Windows)
AIR runtime (needed to run the editor)
The engine comprises a visual story editor and a viewer written in ActionScript 3, that allows creating “Choose Your Own Adventure” style of games, RPG character dialog trees or variants of interactive fiction. It allows the use of variables, conditions and images for the scenes. The viewer has a parser class that can be embedded in any project (respecting the license).