In Botania: Garden of Glass, I created a nether portal (in Creative for testing purposes) and went through it. However, the game crashed! It says 'Shutting down internal server', then produces this crash log.
Crash Log: http://pastebin.com/RXqkPeEd
So the save is corrupt; loading the world again only crashes it again.

FML Log: http://pastebin.com/AuXzDLci