I've added saving of spike times to the NEURON/test.py script, and a script neuroConstruct/pythonScripts/RunTests.py which runs the mod file based cell in nC and compares its spike times against this. There is a match to within 0.01 ms.
I've also changed the save format of the project (latest version of nC needed!) to save as pure NeuroML, so the NML source of the model morphs is stored in hg similar to how the channels are stored, e.g. http://opensourcebrain.org/projects/grancellsolinasetal10/repository/entry/neuroConstruct/morphologies/GranCellSol10_CML.nml.