Matt did already answer you that question, in this thread:
http://www.coniserver.net/ubbthreads/showflat.php?Cat=0&Number=588379&an=0&page=0#588379The answer seems to be "yes" - sphere could work with level geometry with some modifications, at least for the shader. But I wouldn't think about using level geo with sphere that at all, models are much faster than level geometry. Sphere with highest details and a high screen resolution is slow enough
Nevertheless, I think it would be much harder to make the shadows work with levelgeometry, because the shader code doesn't have to be modified too much (at least the ones I use don't have to), but making projected shadows work with levelgeometry could be pretty complicated o_O
Don't listen to me, wait for matt's answer, he knows 100x more + better.
