How much of a closed ecosystem is this?
Sorry for being a little stand off-ish but I've wasted too much time looking into things that turn out to be too closed and not portable enough.
It's part of my problem with scratch/code blocks: you can't easily and obviously cut and paste your code to run in a new place. (although I do use it in grade 6)
I don't want to just teach students to use a software. Heck. I don't even want to just teach them one particular coding language.