Geant4 ElectricField update files: Copy files in the following directories: G4El_EqRhs -----> $G4Install/source/geometry/magneticfield /src and /include G4El_UsualEqRhs -----> $G4Install/source/geometry/magneticfield /src and /include G4ChordFinder -----> $G4Install/source/geometry/magneticfield /src and /include G4ParticleGun -----> $G4Install/source/event /src and /include track/ is the geant4.6.2 version of $G4Install/source/track directory and should be updated