I am very sorry about that. It works just fine if you download the scenario and play on the greenfoot application. I think it has something to do with the way that scenarios are translated to HTML5
I would suggest moving everything from the inner (main) folder out into the outer folder (New Super Mario Bros. Greenfoot). Also, remove the PowerPoint files from within the 'images' folder'.
A new version of this scenario was uploaded on 2019-10-08 11:03:00 UTC
Removed some redundant files from the project folder
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