Developers

I glanced at some of the content types in order to identify the way that the progress or state is saved, but so far I have only found the code for retrieving those two from contentData. How does storing work? 

You have changed localization via semantics.json, haven't you?

Using the library type in semantics.json, you can easily use the editor of other content types. I like that. Is there also a way to a) pass default values to the editor for its options and to b) hide some of its options?