Anyway, I'm hoping the authors see this. I tried Shelly for a while and here's what I think:
1. The tutorial needs background. Its text displayed over more text and that's tough to read. For the first point in the tutorial, I couldn't locate where it was visually and had to carefully read what the various parts of the screen were saying.
2. Make the editor stop complaining while I'm writing something. Its too aggressive and made me immediately think of https://i.redd.it/nygb741tho951.gif.
Overall, I like the concept. I'd have wished the syntax was more like javascript so someone learning this could more easily translate their skills to other parts of the web, but I guess we have to compromise that for the nostalgia and simple commands like `right 90` etc. I love this!