Autodesk Ecotect Analysis - Desktop Tools

[#1]

hello, Im trying to analyse solar radiation in multiple surfaces as shown in the image below.

 

The thing is i work in rhino and am importing my model into ecotect as a dxf - In ecotect I can run this sort of analysis on a single surface with the form fit analysis grid.  When i try to do it without this and try to subdivide my surfaces the analysis takes ages and is usually wrong (all coincident surfaces are blue usually after an analysis that runs for 30 mins and the normals are checked as well) - the only way i can get something similar to the image above is useing geco with grasshopper.  My question is: is this the only way (using either geco or revit) or am I doing something wrong?