Check the readme - what you actually need to do is copy the files from the map2 folder to the FB3 directory, overwriting the current world and replacing it with the new world.
Arik has released 3 files
|Cloud Castle 2: Scarab||D-Mod, Epic||9.6||July 14th, 2014|
|I, Kara Gu||D-Mod, Quest||9.2||July 4th, 2012|
|Cloud Castle||D-Mod, Quest||8.5||February 11th, 2007|