I had a similar issue with the build 42 version:
STACK TRACE
-----------------------------------------
Callframe at: removeFromSquare
function: itemremove -- file: Advanced_trajectory_core.lua line # 838 | MOD: Advanced Trajectory's Realistic Overhaul
function: removeBulletData -- file: Advanced_trajectory_core.lua line # 2437 | MOD: Advanced Trajectory's Realistic Overhaul
function: updateProjectiles -- file: Advanced_trajectory_core.lua line # 2851 | MOD: Advanced Trajectory's Realistic Overhaul
function: checkontick -- file: Advanced_trajectory_core.lua line # 3370 | MOD: Advanced Trajectory's Realistic Overhaul.
[04-01-25 22:50:31.302] ERROR: General f:1757, t:1736027431302> ExceptionLogger.logException> Exception thrown
java.lang.reflect.InvocationTargetException at GeneratedMethodAccessor850.invoke(null:-1).
Stack trace:
jdk.internal.reflect.GeneratedMethodAccessor850.invoke(Unknown Source)
java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.base/java.lang.reflect.Method.invoke(Unknown Source)
se.krka.kahlua.integration.expose.caller.MethodCaller.call(MethodCaller.java:62)
se.krka.kahlua.integration.expose.LuaJavaInvoker.call(LuaJavaInvoker.java:211)
se.krka.kahlua.integration.expose.LuaJavaInvoker.call(LuaJavaInvoker.java:201)
se.krka.kahlua.vm.KahluaThread.callJava(KahluaThread.java:192)
se.krka.kahlua.vm.KahluaThread.luaMainloop(KahluaThread.java:988)
se.krka.kahlua.vm.KahluaThread.call(KahluaThread.java:173)
se.krka.kahlua.vm.KahluaThread.pcall(KahluaThread.java:1963)
se.krka.kahlua.vm.KahluaThread.pcallvoid(KahluaThread.java:1790)
se.krka.kahlua.integration.LuaCaller.pcallvoid(LuaCaller.java:66)
se.krka.kahlua.integration.LuaCaller.protectedCallVoid(LuaCaller.java:139)
zombie.Lua.Event.trigger(Event.java:81)
zombie.Lua.LuaEventManager.triggerEvent(LuaEventManager.java:315)
zombie.gameStates.IngameState.onTick(IngameState.java:1893)
zombie.GameProfiler.invokeAndMeasure(GameProfiler.java:195)
zombie.gameStates.IngameState.updateInternal(IngameState.java:1777)
zombie.gameStates.IngameState.update(IngameState.java:1443)
zombie.gameStates.GameStateMachine.update(GameStateMachine.java:101)
zombie.GameWindow.logic(GameWindow.java:372)
zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:76)
zombie.GameWindow.frameStep(GameWindow.java:917)
zombie.GameWindow.run_ez(GameWindow.java:810)
zombie.GameWindow.mainThread(GameWindow.java:610)
java.base/java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException: Cannot invoke "zombie.iso.IsoChunk.recalcHashCodeObjects()" because "this.square.chunk" is null
zombie.iso.objects.IsoWorldInventoryObject.removeFromSquare(IsoWorldInventoryObject.java:810)
... 26 more



I fixed it by uninstalling "HD Muzzle Flash" and "Shotgun Range Improver" (not sure which caused it) so it's probably an incompatibility with a mod that modifies gun effects.

Update: it wasn't a mod conflict. It's the ballistic/ bullet distance setting. It needs to be between 1.0 and 2.4.

Thanks

what's the minimum and max value for your bullet distance setting when you look at sandbox options? Value can be anywhere from 0 to 10 according sandbox options file.

Ok, I was able to replicate the error. It seems like if the bullet goes too far away and into an unrendered cell/chunk, then the error will occur. It's best to not set the bullet distance value too high.

I'll add a check to delete the bullet if it goes too far.

late response but it should be fixed now