Modifying wall section heights

[pcore]

I am trying to modify a wall type (in section) so that the tops of different materials are at different heights. In the attached image, say that I am trying to make the selected layer of material shorter, how do I do this?

[Scott D Davis]

Click the Modify button, then hover over the top of the wall at that layer, until the line segment over just that layer highlights, then Click. A lock symbol will appear....click to unlock it. Click OK to get out of everything. That wall style can now have the layer ajusted by the "Top Extension Distance" in Properties or by selecting the wall in section and grabbing the blue triangular grip and stretching it.