I'm having trouble using it. I can't see a way to create new files or add dependencies. I see an "Edit Sandbox" button, which takes me to a web version of the app. I can add files and dependencies there, but I can't figure out how to open the editor. Changes to the file structure there also aren't reflected on the app unless I restart it. And, for some reason, any new file I create in the web version is reflected in the app as an empty folder.

I'm not sure what I'm doing wrong here.