Making a Sloped Terrain Feature in HDS8.0

[larq]

I'm coming back to a question that I had posed some time ago. I have since upgraded from HDS7.0 to HDS8.0.

I have a bed of ground ivy stretching the width of my backyard. The dirt surface plane of the ivy is about a foot above the normal ground plane. Connecting these two planes is a slope of river rock. The edge of the ivy bed has curves in it as do the two edges of the river rock feature. Is there a way to slope this river rock band? A wedge would work if it weren't for the curves. I created the river rock feature using a round terrain feature and the break line and change line/arc tools. I don't seem to be able to add elevation lines to this terrain feature. It's not a big deal if I can't do this in 8.0, I'm just looking to make my 3D view more realistic.