Cancel button on import dialog doesn't work

The import button on creating a new world pops up a dialog which can't be closed (at least not with the cancel button).  The game must be force closed.

What I expected to happen was...:
I thought I'd be able to go back to the game

What actually happened was...:
The game minimized

Steps to Reproduce:
1. Click single player.  Since no saves were present, it immediately goes to the new world menu
2. Click More World Options
3. Click Import Settings