I got an error after reading some book, no idea what it is, but hope this can help you patch the mod later

`attempted index: perk of non-table: null
function: update -- file: CDDA Reading.lua line # 9 | MOD: CDDA Reading
java.lang.RuntimeException: attempted index: perk of non-table: null
at se.krka.kahlua.vm.KahluaThread.tableget(KahluaThread.java:1667)
at se.krka.kahlua.vm.KahluaThread.luaMainloop(KahluaThread.java:479)
at se.krka.kahlua.vm.KahluaThread.call(KahluaThread.java:173)
at se.krka.kahlua.vm.KahluaThread.pcall(KahluaThread.java:1963)
at se.krka.kahlua.vm.KahluaThread.pcallvoid(KahluaThread.java:1805)
at se.krka.kahlua.integration.LuaCaller.pcallvoid(LuaCaller.java:38)
at zombie.characters.CharacterTimedActions.LuaTimedActionNew.update(LuaTimedActionNew.java:88)
at zombie.characters.IsoGameCharacter.updateInternal(IsoGameCharacter.java:10350)
at zombie.core.profiling.PerformanceProbes$Invokable$Params1$Probe_Cached.invoke(PerformanceProbes.java:144)
at zombie.characters.IsoGameCharacter.update(IsoGameCharacter.java:9995)
at zombie.characters.IsoPlayer.updateInternal1(IsoPlayer.java:2200)
at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:102)
at zombie.characters.IsoPlayer.update(IsoPlayer.java:2180)
at zombie.MovingObjectUpdateSchedulerUpdateBucket.update(MovingObjectUpdateSchedulerUpdateBucket.java:71)
at zombie.MovingObjectUpdateScheduler.update(MovingObjectUpdateScheduler.java:155)
at zombie.iso.IsoCell.ProcessObjects(IsoCell.java:3058)
at zombie.GameProfiler.invokeAndMeasure(GameProfiler.java:195)
at zombie.iso.IsoCell.updateInternal(IsoCell.java:5955)
at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:102)
at zombie.iso.IsoCell.update(IsoCell.java:5897)
at zombie.iso.IsoWorld.updateWorld(IsoWorld.java:3893)
at zombie.iso.IsoWorld.updateInternal(IsoWorld.java:3993)
at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:102)
at zombie.iso.IsoWorld.update(IsoWorld.java:3917)
at zombie.gameStates.IngameState.updateInternal(IngameState.java:1750)
at zombie.gameStates.IngameState.update(IngameState.java:1443)
at zombie.gameStates.GameStateMachine.update(GameStateMachine.java:101)
at zombie.GameWindow.logic(GameWindow.java:372)
at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:76)
at zombie.GameWindow.frameStep(GameWindow.java:917)
at zombie.GameWindow.run_ez(GameWindow.java:810)
at zombie.GameWindow.mainThread(GameWindow.java:610)
at java.base/java.lang.Thread.run(Unknown Source)
`