A map editor for The Witcher called D'jinni Editor has been made available for download here, and requires the last 1.3 patch.
With it, a new official and free module named The Price of Neutrality, set before the official game, is provided here. It's a bit short (2 hours estimated gameplay time), and there are sometimes bugs with textures (floating eyes and mouths instead of faces are a bit unsettling at first ), but overall it provides for a good atmosphere and two "collector cards" The combats can be fiendishly tough however (more so than in the main game, be sure to take the incineration-enabling Talent in the Ignis Sign tree (I overlooked that and am sorely regretting it, being stuck facing a half-dozen Archespore-types at a time without tactical retreat opportunities).
Witcher free official module and map editor
Moderator: Thanas