Click the green flag. In order to get the hacked blocks click "See Inside" and click the sprite that says "Hacked Blocks" or Hacked Bl... now there should be two (2) blocks in the sprite.
I tried to make my custom block this morning. I used text in based coding which is hard and my first time doing text in based coding. I forgot what website let me create custom blocks for my project. (only appear in this project)