Yes, it's true that while Scintilla.mcc is really powerful, Scribble includes a whole lot of of functionality of its own and it also uses some undocumented components from the MorphOS SDK. It really took a lot of work to get it to where it is now...

I have sometimes contemplated if it would be worth breaking out some of the Scribble functionality to an external class available to other applications. However, this would be quite a bit of work and I'm not sure it would be worth the effort at this stage.

By the way, it is not true that folding in Scribble only works for C/C++. Actually, this depends on the lexer for that particular language. It could however be true that the E lexer does not have this functionality (I'm not at home so I can't check at the moment). If so, this could probably be added without too much difficulty (better ask Leif who wrote this lexer). It would also be possible to improve other aspects of E support but I don't have the time to work on this myself.