Thanks for the answer. I got some really nice results, and once I obtain permission from the setting's owner (its a commission) I will start my own thread.

One thing thing though that I had to work my way through - when creating the Land Bumps and Mountain Bumps layer I ran into problems, and after a few tries I realized your written instructions do not match the 'codified' text highlighted in pink (the order is different), which gives very different results. Once I simply followed the order in the highlighted text everything worked out fine.