I noticed that when I updated your mod, some of my other mods have mobs in the end that have stopped spawning. I am not sure if this a bug with your mod or my other ender mod making their mob spawning more rare in the end.

I haven't changed anything about the way dimension works, but it probably depends on the order mods are loaded - I'll try to make it work better, but if it still doesn't work after the next update, the mods would have to use the API.

thanks

@MinecraftBossKiller Try it with latest update (1.6.2-pre) to see if the fix worked.