I'd love to be able to help you out, only I didn't use CC3 to create this map. I use a vector drawing application called Xara Xtreme.
You might want to search for CC3 tuts in this forum, I do believe there is a tutorial for importing outside scanned or digital image files into CC3 to do your tracings and what not.
Basically what I did, I found an accurate coastline map of Japan (found online) imported it and carefully traced it to achieve the detailed realistic land shape. Then started coloring and placing objects. Somewhat similar to how this would be done in CC3 I am sure.
I hope you find what you need and I hope CC3 does for you what my chosen app does for me - good luck!