Hi there!

I need some help with photoshop. I'm currently working on a map, but I have divided my work into several partitions of that map.
How do I transfer/update the work from the sub-maps to the main map?

Let me explain further...

I have one huge file, with an huge world. I want to extract some of the continents or islands separately and work on it in a new file, then update the huge map with the new layers.

I have an example here:

Main Map = The huge map
Part 1, 2 & 3 = Smaller maps

I can open up both files and drag the layers from the smaller map to the huge map. Then nudge the layers to the right place, delete what I don't want, copy effect, turn of effects, merge layers into one layer - paste effect, rename layer... blabla

Or is there an easier way? I don't want to end up with several land layers and several forest layers.

Thanks in advance!