Can anyone solve this minecraft mod error? - 1

I have Dragon Ball C and mo creature on 1.6.4

---- Minecraft Crash Report ----
// My bad.

Time: 3/9/14 5:59 PM
Description: Initializing game

java.lang.IllegalArgumentException: Failed to register dimension for id 20, One is already registered
at net.minecraftforge.common.DimensionManag…
at JinRyuu.DragonBC.common.mod_DragonBC.loa…
at sun.reflect.NativeMethodAccessorImpl.inv… Method)
at sun.reflect.NativeMethodAccessorImpl.inv… Source)
at sun.reflect.DelegatingMethodAccessorImpl… Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at cpw.mods.fml.common.FMLModContainer.hand…
at sun.reflect.GeneratedMethodAccessor1.inv… Source)
at sun.reflect.DelegatingMethodAccessorImpl… Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventHandler…
at com.google.common.eventbus.SynchronizedE…
at com.google.common.eventbus.EventBus.disp…
at com.google.common.eventbus.EventBus.disp…
at com.google.common.eventbus.EventBus.post…
at cpw.mods.fml.common.LoadController.sendE…
at cpw.mods.fml.common.LoadController.propo…
at sun.reflect.NativeMethodAccessorImpl.inv… Method)
at sun.reflect.NativeMethodAccessorImpl.inv… Source)
at sun.reflect.DelegatingMethodAccessorImpl… Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventHandler…
at com.google.common.eventbus.SynchronizedE…
at com.google.common.eventbus.EventBus.disp…
at com.google.common.eventbus.EventBus.disp…
at com.google.common.eventbus.EventBus.post…
at cpw.mods.fml.common.LoadController.distr…
at cpw.mods.fml.common.Loader.initializeMod…
at cpw.mods.fml.client.FMLClientHandler.fin…
at net.minecraft.client.Minecraft.func_7138…
at net.minecraft.client.Minecraft.func_9999…
at net.minecraft.client.main.Main.main(Sour…
at sun.reflect.NativeMethodAccessorImpl.inv… Method)
at sun.reflect.NativeMethodAccessorImpl.inv… Source)
at sun.reflect.DelegatingMethodAccessorImpl… Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launc…
at net.minecraft.launchwrapper.Launch.main(…

Tony

Go to the configs of DragonBC (.minecraft\config) and look for something that says dimension, change it to something else than 20,
if you can't find it in the DragonBC config then look in the configs of other mods that add dimensions and change the number 20 there

Bas