Updating Geant4 and finding new class to inherit from

Hello,
I am using Ubuntu 18.04. I have a Geant4 application that builds under Geant4.10.02.p03.

I am trying to update the application to build at 10.04.

I have a couple of classes that use or inherit from G4eLowEnergyLoss and G4LowEnergyBremsstrahlung.

These classes appear to have been removed from version 10.04. I guess I could cheat and find the relevant files in the older release and copy them to my src and include directory. However, I tried this before and it led to more problems further down the line and besides these files have been removed for a reason - right ?

So how do I find which classes I should use or inherit from now ? I tried inheriting from classes higher up, but without great success.

Many thanks in advance
Chris