got CC and Fractal Terrains. Trying to build a world map using FT the generate "smaller" maps for CC. I use hexagon grid at the lowest level.

I am trying to get the following result:
level 1) Fractal Terrains - World map
level 2) CC maps on which I can put a hexagon grid - Overland Movement map
level 3) CC map a zoom of a single hex from level 2 also on a hexagon grid - Overland Situation Map

My problem is scale. I would like the level 3 to be about 20km across, using 20x1km hexes. This means of course that level 1 hex is 20km across. How do i set up Fractal Terrains to generate maps in CC that I can overlay with a 20km/hex grid? Also is there a way to generate a next level map from CC?