Hey Shawn -

Thanks for your response. Have to admit, I'm feeling like a complete idiot not being able to figure this out.

Here's three images. The first is how the interface appears when I go into the editor. The second is an example of what I'm trying to do. Basically I want to create a simple terrain with a creek running through it. That much I can make happen, as you can see. Then what I want to do is soften the edges of the creek bed with the effects painting brushes. Image three shows how I'm trying to do that, but nothing happens. The brush acts like it's trying to paint, but no effect shows up. By the way, if it matters, I've got the rock hardness set pretty low in the Effects Tab if that matters.

Any suggestions are appreciated.