I go to the nether an after a little bit the game crashes.

I go to the nether an after a little bit the game crashes. crash does not happen if i go back to the over world.

What I expected to happen was...:
the game to not crash

What actually happened was...:
The game crashed

Steps to Reproduce:
1. Go to the Nether
2. Wait a bit.

Time for crash varies
On one game, it starts in the Nether and immediately crashes.
In another downloaded map the game seems to crash in one place in particular.
Problem did not start till that map was downloaded.
Map is Gloria 2.

Fixed problem by force updating