I try load or start new world. I end up get reject by this mod. This shouldn't be happen when i using singleplayer.
[12:13:05] [Server thread/INFO]: Sagez lost connection: Mod rejections [FMLMod:nibbler{0.4}]

latest.log
fml-client-latest.log

So.. What do I need to do something with nibbler?

Nope. I just uploaded the fix. There will be a 0.4.1 version soon. You can also revert to 0.3 as a quick work around haha.

Hmm that's an easy fix. Must have just misunderstood the accepted remote version stuff.