It can be very useful to let Gauss write out MCParticles in the Generation directly (without the detector simulation), which then can be analysed. This can be achieved the following way (write this at the end of your version of Gauss-Job.py):

gtos = GenerationToSimulation()
gtos.SkipGeant = True
gs = GaudiSequencer("GenMonitor")
MCTruthStream = OutputStream("MCTruthStream")
MCTruthStream.ItemList += [ "/Event/Gen#1", "/Event/Gen/HepMCEvents#1", "/Event/MC#1", "/Event/MC/Header#1", "/Event/MC/Particles#1", "/Event/MC/Vertices#1" ]
MCTruthStream.Output = "DATAFILE='MCTruth.sim' TYP='POOL_ROOTTREE' OPT='RECREATE'"
gs.Members += [ SimInit(), gtos, MCTruthStream ]

The root file can then be run over with an MCTupleTool in DaVinci (with certain restrictions, i.e. only tools which only access 4-vectors will run…)