Error al ejecutar Minecraft 1.7.2 Forge

Hola.
He instalado el Forge 10.12.2.1121 y no puedo arrancar Minecraft, ni siquiera sin los mods.

Me da el error siguente:

*** MagicMinecraftLauncher 1.2.5 ***
LCP: ;C:\Users\H￩ctor\AppData\Roaming\.minecraft\versions\1.7.2-Forge10.12.2.1121\1.7.2-Forge10.12.2.1121.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\minecraftforge\forge\1.7.2-10.12.2.1121\forge-1.7.2-10.12.2.1121.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\minecraft\launchwrapper\1.9\launchwrapper-1.9.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\ow2\asm\asm-all\4.1\asm-all-4.1.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\scala-lang\scala-library\2.10.2\scala-library-2.10.2.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\scala-lang\scala-compiler\2.10.2\scala-compiler-2.10.2.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\java3d\vecmath\1.3.1\vecmath-1.3.1.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\sf\trove4j\trove4j\3.0.3\trove4j-3.0.3.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\ibm\icu\icu4j-core-mojang\51.2\icu4j-core-mojang-51.2.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\sf\jopt-simple\jopt-simple\4.5\jopt-simple-4.5.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\lzma\lzma.0.1\lzma-0.0.1.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\paulscode\codecjorbis\20101023\codecjorbis-20101023.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\paulscode\codecwav\20101023\codecwav-20101023.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\paulscode\libraryjavasound\20101123\libraryjavasound-20101123.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\paulscode\librarylwjglopenal\20100824\librarylwjglopenal-20100824.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\paulscode\soundsystem\20120107\soundsystem-20120107.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\io\netty\netty-all\4.0.10.Final\netty-all-4.0.10.Final.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\google\guava\guava\15.0\guava-15.0.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\apache\commons\commons-lang3\3.1\commons-lang3-3.1.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\commons-io\commons-io\2.4\commons-io-2.4.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\java\jinput\jinput\2.0.5\jinput-2.0.5.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\java\jutils\jutils\1.0.0\jutils-1.0.0.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\google\code\gson\gson\2.2.4\gson-2.2.4.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\com\mojang\authlib\1.3\authlib-1.3.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\apache\logging\log4j\log4j-api\2.0-beta9\log4j-api-2.0-beta9.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\apache\logging\log4j\log4j-core\2.0-beta9\log4j-core-2.0-beta9.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\lwjgl\lwjgl\lwjgl\2.9.0\lwjgl-2.9.0.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\lwjgl\lwjgl\lwjgl_util\2.9.0\lwjgl_util-2.9.0.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\org\lwjgl\lwjgl\lwjgl-platform\2.9.0\lwjgl-platform-2.9.0-natives-windows.jar;C:\Users\H￩ctor\AppData\Roaming\.minecraft\libraries\net\java\jinput\jinput-platform\2.0.5\jinput-platform-2.0.5-natives-windows.jar
ShowLog: true
InactiveExtMods: CustomMobSpawner 3.2.0.zip;DrZharks MoCreatures Mod v6.2.1.zip
MainClass: net.minecraft.launchwrapper.Launch
Restoring disabled mods: mods
Disable inactive mods: mods
Disabled: CustomMobSpawner 3.2.0.zip
Disabled: DrZharks MoCreatures Mod v6.2.1.zip
Restoring disabled mods: coremods
Disable inactive mods: coremods
[19:08:19] [main/INFO]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[19:08:19] [main/INFO]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[19:08:19] [main/INFO]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker
[19:08:19] [main/INFO]: Forge Mod Loader version 7.2.211.1121 for Minecraft 1.7.2 loading
[19:08:19] [main/INFO]: Java is Java HotSpot(TM) 64-Bit Server VM, version 1.8.0_20, running on Windows 8.1:amd64:6.3, installed at C:\Program Files\Java\jre1.8.0_20
[19:08:19] [main/INFO]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[19:08:19] [main/INFO]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker
[19:08:19] [main/INFO]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[19:08:19] [main/ERROR]: Unable to launch
java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_20] at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_20] at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-1.9.jar:?] at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_20] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_20] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_20] at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_20] at magic.launcher.Launcher.main(SourceFile:207) [MagicLauncher_1.2.5%20(1).jar:?] *** Main class main() finished ***