Update: Beta testing for FOREground is now closed. Thanks for your interest!
We are currently in beta testing for FOREground, a Revit application designed to assist with site and landscape modeling and documentation. We are specifically looking for landscape architects that have experience with Revit. So if you are a landscape architect that would be interested in beta testing an awesome new toolset for Revit, please get in touch by filling out this contact form.
While browsing through a Revit Forum post, I noticed that someone mentioned an app that could align Topo to Slab Edges. A quick search on the Autodesk Exchange turned up the Topo Align app.
I have not yet had the chance to test it out myself, but even after just briefly looking at its features, it seems like a very worthwhile Revit add-in. And for a cost of only 1.99 USD, it is also a really good deal. If you frequently work with Toposurfaces, I highly recommend that you check it out.