I read a really interesting thread on the adesk forums not long ago about the challenges of assigning cubicles as rooms within revit, as they don't have walls, per se, but, would be counted as their own spaces with FM Desktop or other CAFM programs.
Those who replied gave options on what could be done, and there was a fabulous document posted about Revit Rooms and how they work with Autodesk FMDesktop.
Enjoy!