I ran the adventure in FR as well. I put cauldron in the Thunder peaks right in between cormyr and the dale lands.
Used the same god transformation as Lazybones.
and instead of using the harpers i created a new guild called the Striders of Tymora. added some new flavor to the world...
and basically the thunderpeaks are big enough that i dont think it should be too difficult to fit the area of cauldron in it.