Avoid negative total event time
Avoid negative total event time

Closes #191

LukeWoodward/rg2,Maprunner/rg2,Maprunner/rg2,MaBreaker/rg2,MaBreaker/rg2,LukeWoodward/rg2,Maprunner/rg2,MaBreaker/rg2,LukeWoodward/rg2