You don't need to use bucklescript toolchain to write Ocaml, it has a very good package manager, the build-system tooling is getting better, already has great editor support for many years now(merlin).
I think the tooling scene is much better than Haskell. Not sure what you mean by "no forward references"?
I'm guessing they are talking about having implicit mutual recursion between items in a module, like Haskell has.
I probably got the name wrong, but it's the ability to use a function before it is defined.
In OCaml/ReasonML, you'd have to use the rec keyword and structure your codebase in a particular way to define mutually-recursive functions. It is a small but noticeable papercut, especially since recursion is so common in a functional language.