You use GTK or Jk2radiant ?
There's no proof of making blended terrains to jk2. All of the easygen tutorials uses GTKradiant for Q3/RTCW maps.
However its easy to get a terrain like in the kejim_post with easygen. I'll explain it here.
Create your map by manual or heightmap method. Doesn't matter. Use only one texture. When you click Exp Map button, check "insert into a skybox" and "add an info player start" options.
You don't have to change metashader and alphamap crap cuz it's not necessary for one textured terrains.
The important thing is you need to set the texture in the Shader section.
For example, write "yavin/rock3" for top and write "system/caulk" for bottom, sides instead of "common/terrain" and "common/caulk".
Click continue. Select your maps name and save it.
Open it up with your jk2radiant/gtkradiant. Select the sky shader for the box around the terrain. You will notice the terrain looks fine and bottom and sides are textured with caulk. However you need to select the terrain and hit N key (in jk2radiant). Delete every key except "classname","func_group". Set your "_color" and "ambient" keys for the worldspawn for a global light and you're done. Save your map and compile it.
You can delete the vertexmapshader keys of worldspawn, too.
My example with only the terrain and skybox took 2 minutes and 51 seconds on win98-celeron333-96ram system.
Here are some screenshots. Well it's a bit smooth one. Low hills.
http://www.geocities.com/fayebo80/stuff/shot0003.jpg)
http://www.geocities.com/fayebo80/stuff/shot0004.jpg)
http://www.geocities.com/fayebo80/stuff/shot0005.jpg)
http://www.geocities.com/fayebo80/stuff/shot0006.jpg)
http://www.geocities.com/fayebo80/stuff/shot0007.jpg)
http://www.geocities.com/fayebo80/stuff/shot0008.jpg)