Things disappear If I quit the game.

Things I build dissapear If I Close the game.
The bug happens both on survival and creative.

It should have saved.

What actually happened was...:
I had just gotten the 0.6.0 alpha update and then
I played and built things. I quitted to title.I turned
on fancy graphics so I can get clouds. Later
on I played again and what I built was gone.

The glitch had to do something with the
fancy graphics or the clouds.

Steps to Reproduce:
1. Get 0.6.0 alpha update for pocket edition.
2. Turn on fancy graphics.
3. Build things creative or survival.
4. Quit the game.
5. Go back on to the world you had built
on.
6. What you have built dissapeared.