With the assets and terrain I created I started importing the buildings into UDK to rough out the early stages of my level design. The ability to bring the elements together so quickly, focus on building placement and then jump into your level and walk around, was a dream in UDK. Preview mode gives a whole new perspective on how your assets will look in-game and gives immediate feedback on whether the placement of your assets will work.
There's still a lot of work to do including, optimising, UV mapping, and texturing but as an initial start to my level design I'm pretty pleased with the results. I imported all the elements into a new scene in 3DS max to get a better render of the environment and experiment with a plane with a water material to create an ocean around my islands.