Working in 2010. I created a copy of the existing grade toposurface, and raised it above the existing to represent the zoning height limit. It was placed on a separate workset to allow visibility control, and given a new material that is mostly transparent so you can see the building below it. That way I can show the zoning police that no portion of my new building exceeds the height limit above existing grade.
Now I need to add a subregion to the existing grade toposurface, and can't. Automatically, all subregions get attached to the one that is 35' in the air - I guess becase that is the most recently created one. I've tried making sure the one I want the subregion to be associated with is the only one visible in the view; I've tried using phasing to force the subregion onto the correct toposurface, all to no avail. I've tried changing the workset the subregion is placed on, but can't get to it to change that parameter. If I have to I'll delete the "height limit" toposurface, then recreate it again later. Before I do, any ideas on how to control which toposurface gets the subregion?