Looks like a standalone app as opposed to a web library, unless I misread.
In any case, we don't typically offer compatibility with X markdown editor or whatnot for a variety of reasons:
Markdown can be disabled in favour of other parsing languages (like BBCode, etc)
There needs to be support for post-related functions offered by the existing composer, such as topic images, file uploads, tags support, etc.
The short of it is, it takes quite a bit of work to ensure compatibility and full functionality, which is why at current we only support default and redactor.
Imgur