Thank you for MCA 5.0.7-1.8 release.
but...but..my #467 problem still appeared on starting game with MCA.
I tried to install newer forge , and remove unrelated mods and resourcepacks, but It looks same situation for now.
I hope that something can cooperate.
Here is crash report.

---- Minecraft Crash Report ----
// There are four lights!

Time: 15/08/24 23:21
Description: Exception ticking world

java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429)
at java.util.HashMap$KeyIterator.next(HashMap.java:1453)
at com.google.common.collect.AbstractMapBasedMultimap$WrappedCollection$WrappedIterator.next(AbstractMapBasedMultimap.java:486)
at net.minecraft.util.ClassInheritanceMultiMap$2.computeNext(SourceFile:90)
at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143)
at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138)
at net.minecraft.world.World.func_175650_b(World.java:3126)
at net.minecraft.world.chunk.Chunk.func_76631_c(Chunk.java:952)
at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:46)
at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:12)
at net.minecraftforge.common.util.AsynchronousExecutor.skipQueue(AsynchronousExecutor.java:344)
at net.minecraftforge.common.util.AsynchronousExecutor.getSkipQueue(AsynchronousExecutor.java:302)
at net.minecraftforge.common.chunkio.ChunkIOExecutor.syncChunkLoad(ChunkIOExecutor.java:12)
at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:117)
at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:92)
at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:189)
at net.minecraft.world.World.func_72964_e(World.java:304)
at net.minecraft.world.World.func_175726_f(World.java:299)
at net.minecraft.world.World.func_180495_p(World.java:837)
at net.minecraft.village.Village.func_179860_f(SourceFile:326)
at net.minecraft.village.Village.func_75557_k(SourceFile:312)
at net.minecraft.village.Village.func_75560_a(SourceFile:69)
at net.minecraft.village.VillageCollection.func_75544_a(SourceFile:60)
at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:225)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:693)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:598)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:164)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:478)
at java.lang.Thread.run(Thread.java:745)

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Stacktrace:
at java.util.HashMap$HashIterator.nextNode(HashMap.java:1429)
at java.util.HashMap$KeyIterator.next(HashMap.java:1453)
at com.google.common.collect.AbstractMapBasedMultimap$WrappedCollection$WrappedIterator.next(AbstractMapBasedMultimap.java:486)
at net.minecraft.util.ClassInheritanceMultiMap$2.computeNext(SourceFile:90)
at com.google.common.collect.AbstractIterator.tryToComputeNext(AbstractIterator.java:143)
at com.google.common.collect.AbstractIterator.hasNext(AbstractIterator.java:138)
at net.minecraft.world.World.func_175650_b(World.java:3126)
at net.minecraft.world.chunk.Chunk.func_76631_c(Chunk.java:952)
at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:46)
at net.minecraftforge.common.chunkio.ChunkIOProvider.callStage2(ChunkIOProvider.java:12)
at net.minecraftforge.common.util.AsynchronousExecutor.skipQueue(AsynchronousExecutor.java:344)
at net.minecraftforge.common.util.AsynchronousExecutor.getSkipQueue(AsynchronousExecutor.java:302)
at net.minecraftforge.common.chunkio.ChunkIOExecutor.syncChunkLoad(ChunkIOExecutor.java:12)
at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:117)
at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:92)
at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:189)
at net.minecraft.world.World.func_72964_e(World.java:304)
at net.minecraft.world.World.func_175726_f(World.java:299)
at net.minecraft.world.World.func_180495_p(World.java:837)
at net.minecraft.village.Village.func_179860_f(SourceFile:326)
at net.minecraft.village.Village.func_75557_k(SourceFile:312)
at net.minecraft.village.Village.func_75560_a(SourceFile:69)
at net.minecraft.village.VillageCollection.func_75544_a(SourceFile:60)
at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:225)

-- Affected level --
Details:
Level name: New World001
All players: 0 total; []
Chunk stats: ServerChunkCache: 626 Drop: 0
Level seed: -8918104364449433835
Level generator: ID 00 - default, ver 1. Features enabled: true
Level generator options:
Level spawn location: -18.00,64.00,262.00 - World: (-18,64,262), Chunk: (at 14,4,6 in -2,16; contains blocks -32,0,256 to -17,255,271), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 10389157 game time, 12325404 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 88178 (now: false), thunder time: 76775 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:693)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:598)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:164)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:478)
at java.lang.Thread.run(Thread.java:745)

-- System Details --
Details:
Minecraft Version: 1.8
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 239732776 bytes (228 MB) / 583176192 bytes (556 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
FML: MCP v9.10 FML v8.0.99.99 Minecraft Forge 11.14.3.1450 5 mods loaded, 5 mods active
States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
UCHIJAAAAAAAAA mcp{9.05} Minecraft Coder Pack
UCHIJAAAAAAAAA FML{8.0.99.99} Forge Mod Loader
UCHIJAAAAAAAAA Forge{11.14.3.1450} Minecraft Forge
UCHIJAAAAAAAAA RadixCore{1.8-2.0.4} RadixCore
UCHIJAAAAAAAAA MCA{1.8-5.0.7} Minecraft Comes Alive
Loaded coremods (and transformers):
GL info: ERROR RuntimeException: No OpenGL context found in the current thread.
Profiler Position: N/A (disabled)
Player Count: 0 / 8; []
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'fml,forge'

It has to do with something about the overwrite villager thing on the mod config menu
whenever i turn it off. old worlds seem to work. and when i select "true" it goes bonkers and kicks me out of minecraft. guess minecraft doesnt want the squidwards to dissappear

Needs review, maybe I can do something about this.

MCA for 1.8 has been updated, give that a try and if the issue occurs come back.

Just to make sure, are you starting a new world on loading an old one?

Thanks for reply. The meaning that two Minecraft processes ran at the same time?
(The one is new world with MCA , The other one is try to start old world and crash.)
If that's right, The answer is No.

But... I tested again. Because, certainly, I was also playing new world with MCA.
It wasn't the same time with starting old world, but if a process is living background, it may be its situation.
(I don't know whether there is such thing.)

The condition is below.

• Install MCA 1.8-5.0.7.1
• Delete the crashed world data, and restore from backup.(I'm doing this each time.)
• Reboot the PC , and run minecraft, and start the old world game.

The result was same situation....X(