Window Generator 2 (Classic)

This is an adapted version of the add-on 'Window Generator 2' (author: SayPRODUCTIONS, Antonio Vazquez (antonioya)) under the blender 2.8. Everything you liked about that old version (Version 2.0. Blender 2.6.3) is now available in 2.8. 

- Added ability to save settings to 'Operator Presets