BE SURE TO TURN ON TURBO MODE AFTER PRESSING [S] TO START (shift + click on green flag to enable it) If the project succesfully detects that you have either a gray/white or green background, then it will replace it with a dithered rainbow pattern. If it doesn't, don't worry. You can still try the "custom background color" feature, just click "See inside", and then click on the "renderer" sprite. You should see a custom block definition for "accuraterender:custom", You also should see a note that says "Change to the color of your choice", There's a Color detector boolean block near the note. click the current color it has and change it to the color of your background. Then run the code with the custom block "accuraterender:custom". WARNING: Might be laggy because the code for it has "Run without screen refresh" enabled by default.