Yes, you can make your elevations manually, too. I have made all elevations manually to my Finland-Russia map (256 X 256 miles). It was big work, but result is cool looking (It is coming to Combat Theater soon)!
Of course I looked World-Atlas to make correct elevations in different areas. My map scale is 1:4 and I made elevations in some areas three times bigger than they are in normal world. That's because Finland Russia area is mostly very flat. Only in North Finland and Norway coastline is hills and mountains. There my elevations are only two times bigger.
You can use Terrain Editor Tools to make natural looking hills and mountains:
1) First use Terrain tool "Set Alt" and set there the LOWEST alt of your area what you are editing, for ex. "500" (ft). Near water use settings "0 - 100", because water is alway 0-level.
2) Then Click "Setup Filter". There you see three equal looking boxes: "Sin Wave, Saw Tooth and Square Wave". If you want natural looking hills and mountains, use only "Sin Wave".
3) Set from "Alt Feet" the elevation variation (height: for ex. 800 ft). Then click X and Y boxes active and set Xmiles (length: for ex. 4.800) and Y-miles (wide: for ex. 3.700). That makes nice looking "round-type" hills.
4) In the bottom of "Setup Filter" window is "Enable Transition" box. Active it and set "Number of Transition verticles" for ex. "4". Then active 1-4 "Apply Transition to" boxes. They are "points of the compass" where your transition affects! Normally I click all the 4 boxes.
5) Write your settings down (pen and paper:-) and close the "Setup Filter" Window by clicking OK.
6) Drag some BIG area (for ex. 20 X 20 miles) in your terrain active with your left mouse button and then click "Perform Op".
7) And look: you have nice looking hill area in your terrain! :-)
It is now very regular looking: all the hills are in rows and same altitude. You must broke this regularity by using here and there other settings in "Setup Filter" windows (Sine Wave) "Alt Feet", "X-miles" and "Y-miles".
Don't care very much water areas when you work with elevations (You maybe have some water hills:-). You can always put them back to 0 -level by using "Water not 0" tool!
I "blowed" my Finland-Russia map terrain (each different looking areas) about five to ten times with different settings and now it's very natural (irregular) looking!
If you want my map to look the elevations and some other ideas, write to me:
ismo@kesalesket.netI cand send the FinRus.res file to you!;)