Forge 1.7.2 wont open

[Firelord6]

Minecraft Forge 1.7.2 doesnt want to open, i put the Star Wars mod in the mods folder (the version for 1.7.2) and i start up the launcher and click play (With Forge 1.7.2) and the launcher closes, nothing more happened, so i did it again, but ths time with the setting so the launcher would close. And i got this:

[13:00:44] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[13:00:44] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[13:00:44] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker

[13:00:44] [main/INFO] [FML]: Forge Mod Loader version 7.2.211.1121 for Minecraft 1.7.2 loading

[13:00:44] [main/INFO] [FML]: Java is Java HotSpot Client VM, version 1.8.0_73, running on Windows 7:x86:6.1, installed at C:\Program Files (x86)\Java\jre1.8.0_73

[13:00:44] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[13:00:44] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker

[13:00:44] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[13:00:44] [main/ERROR] [LaunchWrapper]: Unable to launch

java.util.ConcurrentModificationException

at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_73]

at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_73]

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:?]

Java HotSpot Client VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

 

Notice the unable to launch error. I want help so i can run forge 1.7.2. Thanks

[Firelord6]

why not?

[Firelord6]

I needed a mod for 1.7.2, it worked fine in 1.7.10. But the only thing it did was crash