I have been following Arsheesh's Eriond tutorial to get a good height map, and finally managed to get rivers to work on Wilbur. I didn't follow the steps to the letter because I prefer to work in Paint.Net as much as possible, even though it isn't as versatile, since my computer freezes up too much with GIMP. But I did need GIMP for the airbrushing part.

I still need to fix some of the rivers since I Wilburfied the map in quarters to preserve detail without having Wilbur crash on me. If you look really closely at the map you can see rivers that start small, begin to grow, and then stop abruptly in the middle of a landmass when they reach the halfway point on the map.

Altitude Map for CG_preview.png

But overall I'm really pleased with how it turned out!

Here it is converted into 8 (or 9?) shades of grey in preparation for working with climates. I see a lot of work in my future...

Average Altitude for CG_preview.png