I have a problem, nothing happened when I clicked the start button
This is a bug that happens if your settings are configured incorrectly. I am fixing it right now, so you don't have to do this!Turn your render distance to 16 chunks and make sure you are playing on the latest snapshot.Does it work now?
EDIT: Couldn't necessarily "fix" this bug, so I added a little warning saying that you have to turn it to 16 chunks in a new update.
This should solve all of the complaints.