Yeah...I was following your tutorial, step by step, and cross referencing the ascension map tutorial which does it slightly different using embossed layers. The embossing is pretty harsh, but depending on your starting layer, it looks pretty neat. What you see above is my experiment with your tutorial and RobA's recommendation using the 5px lines and dilating, then I used both embossing and height maps to compare. This was just an experiment to see if I could make a cone-volcano with ridges. To be perfectly honest, it's way too symmetrical but I just wanted to show how easily its done: no special steps, I just cut a fuzzy hole out of the middle and filled with black.
I've followed this tutorial, I might be somewhat of a novice map maker but this is a wonderful addition. Though for me It will take some tweaking for world wide maps. I am definitely going to use it for my smaller regional maps.