The default option on the behavior pack dialogue box is the option the game is saying not to click on in the new create new world screen.

How to reproduce:

1. Create a new world with a marketplace template
2. Unlock the creators settings
3. Remove the behavior pack
4. Observe the default option is the OK button

Observed results:

The default option is the OK button

Expected results:

The default option should be the Cancel button, matching the behavior of other dialogue boxes