Hello,
1.
Create a sub-directory called RegCM/PreProc/DATA/RegCM
link on RegCM/PracticeRun/output/ to the RegCM/PreProc/DATA/RegCM

2.
Edit the domain.param
DATTYP='FNEST'
Run the terrain.x script
you need I,J and K to the OUT_HEAD.ctl

3.
Make a second level subdirectory RegCM/Nest

4.
Run icbc.x script

5.
In the new subdirectory Nest copy the two files, regcm.in and regcm.x, from the Commons sudbirectory