Revit MEP's Space object has a parameter called 'Average Estimated Illumination' that is computed using the Zonal Cavity Method, based on the fixtures in the Space, and their associated .ies photometry. Refer to page 281 of the Imperial Tutorials.
Ceiling hosted lights need to have have 'Openings' to cut the ceiling. Face hosted lights hosted on linked ceilings need to have a slight extrusion below the ceiling plane (to make it visible) since it is not possible at present to cut a linked ceiling with an 'Opening'.
As for Export to IES VE, this is accomplished via File > Export > Send Model to IES
. Additionally, you can download a trial from http://www.iesve.com.
Martin Schmid
Product Line Manager
Mechanical Detailing and Electrical Design
Architecture, Engineering, and Construction
Autodesk, Inc.