Using the border select dialog (For a JPanel for example) causes unicode chars inside any form controls to become a square (For example hebrew chars which work ok otherwise, they do get escaped in the source code when you type them in the designer but work correctly even when escaped).
1. Create a JFrame.
2. Add a button for example and edit its label to something using unicode chars, like something in hebrew.
3. Add a JPanel and change it's border via the border select dialog (Properties), I used a TitledBorder for example.
WindowBuilder Pro stable v8.0.0