Crash when trying to start world (single or multiplayer)

Put the summary of the bug you're having here

What I expected to happen was...: .. That I would be able to use the game less than 24hrs after purchase.

What actually happened was...:
The game failed to start the world

Steps to Reproduce:
1. Start the game
2. ... hit single or multiplayer
3. ... try to load a world and CRASH!