Crash with custom preset

When creating a superflat world with a custom preset (one that has fire then leaf blocks then 2 layers of gravel) it will load and be happy for ~3 seconds, then the game will crash, not every time I load that world the game crashes

What I expected to happen was...:
world loads as expected

What actually happened was...:
world loads and starts doing what is expected then crashes

Steps to Reproduce:
1. Create world with this preset "2;51,161,2x13;1;decoration"
2. load world
3. crash