If I had one map I wanted to draw more maps around, I would insert a bmp, on the bmp layer, in the center of the template.
That shows me where the rivers, mountains, roads, etc. go off that map.
I then draw within each template area within each rectangle.
Note that I also save to multiple file names when I make changes. Make a few changes, save to filename0002,fcw, make a few more changes, save to filename0003.fcw, etc. This makes it very easy to deal with errors, and gee do I make errors.