You would not want to migrate your project from 4.13.1 to 4.14.0 Preview 3. You’d want to migrate it to another 4.13 project, and then try 4.14 (when it’s released). Preview builds are known to have issues with them, that’s why they’re previews. 
Did you try a new project in 4.13 as well?
Please update the newest builds as a .txt file, thank you!