G4PSFlatSurfaceFlux for GDML or Tessellated geometries

Dear all,

I’m defining a multifunctional detector together with a couple of primitive scorers for a volume in a GDML geometry. The scorers I’m using are G4PSEnergyDeposit, G4PSDoseDeposit, and I’m trying to add G4PSFlatSurfaceFlux with filters to get fluxes for electrons, positrons, protons, and gamma. In the end of a run, I see that there was deposited energy in the volume, but all the fluxes remain zero. Even when I add filters to G4PSEnergyDeposit in order to identify the main player in energy deposit, I see that the respective flux remains zero.
I read that G4PSFlatSurfaceCurrent for example works only with G4Box (and therefore my assumption is that it won’t work for a volume in a GDML geometry, even if it’s itself a box). Is that also true for G4PSFlatSurfaceFlux? The respective section in the documentation makes no mention of it.
Finally, the G4PSCellFlux works, but my goal is to get the fluxes of particles that reach the volume, and my fear is that G4PSCellFlux will include tracks generated inside the volume. Is that a correct conclusion?

Many thanks in advance.