We are currently investigating reimplementing the 'Tinsel' engine, as used by Discworld 1 and 2.
Ender is organizing this.
The rights situation has been resolved, and Terry Pratchett and his agent Colin Smythe have approved the source release and future freeware re-issuing of the game.
We are currently awaiting receipt of the engine source code.
Around October 2005 we learned that the source code has been successfully located and started waiting for it to be sorted and sent to us.
As of this update, 2nd January 2007, we are still awaiting delivery of the source code. Additional attempts to locate a second copy of the code have not been successful, and we are now waiting on final word on whether the code we have located will ever be released. If not, a more serious attempt at reverse engineering will be made, although the time this process takes cannot be estimated.
In short, we have all the approval needed to move forward with supporting the game and making Discworld freeware. However Discworld is NOT freeware at the moment. It may be in the future, assuming all goes according to plan.
Whether the gamedata release will have a DFSG/OSI compatible license remains to be determined.