Thanks a lot for your explanations.

I am afraid, however, that I am way too green in the use of raster programs to make good use of it today, but I will copy / paste your post on the side and review it after I understand better how these software work.

This looks anyway a terrific process to transform a locale map into a Shadowfell version, so I will try to keep my character in the mortal world until I can reproduce it (hopefully before I turn into old age or undeath myself)!

Thanks again for your time.