Editor Won't Launch or Package Game - Fatal Error

Development Programming & Scripting
1

I’ve been trying to run my game outside of the editor which has been working previously, but since implementing a settings menu I am no longer able to. Playing any level inside of the editor works consistently.

Here is the error I get when attempting to launch:

    LogPlayLevel: [2018.03.07-01.23.22:976][  0]LogWindows: Error: begin: stack for UAT
    LogPlayLevel: [2018.03.07-01.23.22:976][  0]LogWindows: Error: === Critical error: ===
    LogPlayLevel: [2018.03.07-01.23.22:976][  0]LogWindows: Error:
    LogPlayLevel: [2018.03.07-01.23.22:976][  0]LogWindows: Error: Fatal error: [File:D:\Build\++UE4+Release-4.18+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp] [Line: 725]
    LogPlayLevel: [2018.03.07-01.23.22:976][  0]LogWindows: Error: Invalid state transition 2 1 with /Script/MaterialShaderQualitySettings/ShaderPlatformQualitySettings when it has already been processed.

Here is a section of the output log I get when attempting to package:

UATHelper: Packaging (Windows (64-bit)):       FoliageSpawner_C /Game/RPG/Example_Map/FloatingIsland_2.FloatingIsland_2:PersistentLevel.FoliageSpawner27
UATHelper: Packaging (Windows (64-bit)):   
UATHelper: Packaging (Windows (64-bit)):       Function /Game/RPG/blueprints/FoliageSpawner.FoliageSpawner_C:UserConstructionScript:02AB
UATHelper: Packaging (Windows (64-bit)):   LogInit: Display: LogScript: Warning: Runaway loop detected (over 1,000,000 iterations) - see log for stack trace
UATHelper: Packaging (Windows (64-bit)):   
UATHelper: Packaging (Windows (64-bit)):       FoliageSpawner_C /Game/RPG/Example_Map/FloatingIsland_2.FloatingIsland_2:PersistentLevel.FoliageSpawner28
UATHelper: Packaging (Windows (64-bit)):   
UATHelper: Packaging (Windows (64-bit)):       Function /Game/RPG/blueprints/FoliageSpawner.FoliageSpawner_C:UserConstructionScript:02AB
UATHelper: Packaging (Windows (64-bit)):   LogInit: Display:
UATHelper: Packaging (Windows (64-bit)):   LogInit: Display: Failure - 78 error(s), 35 warning(s)
UATHelper: Packaging (Windows (64-bit)):   LogInit: Display:
UATHelper: Packaging (Windows (64-bit)):   
UATHelper: Packaging (Windows (64-bit)):   Execution of commandlet took:  108.94 seconds
UATHelper: Packaging (Windows (64-bit)): Took 126.2392205s to run UE4Editor-Cmd.exe, ExitCode=1
UATHelper: Packaging (Windows (64-bit)): Cook failed. Deleting cooked data.
UATHelper: Packaging (Windows (64-bit)): ERROR: Cook failed.
UATHelper: Packaging (Windows (64-bit)):        (see C:\Users\<username>\AppData\Roaming\Unreal Engine\AutomationTool\Logs\E+Program+Files+(x86)+Epic+Games+UE_4.18\UAT_Log.txt for full exception trace)
UATHelper: Packaging (Windows (64-bit)): AutomationTool exiting with ExitCode=25 (Error_UnknownCookFailure)
UATHelper: Packaging (Windows (64-bit)): BUILD FAILED
PackagingResults: Error: Unknown Cook Failure

I have tried removing all references to the settings menu I made so it should have no bearing on the game, but the errors persist. Any thoughts? Happy to provide additional info if needed.

Thanks in advance.