Importing Markdown files with images?

Hello,
I’m trying to import markdown that contains images using the /markdown command. According to the documentation images are supported but I can’t make this work.
The documentation contains this:

What is the /asset directory? A special directory?
I tried:

  • relative path to such a images/x.jpeg
  • absolute path such a /x/y/images/x.jpeg
  • relative path with . such as ./images/x.jpeg
    All images statement are ignored without any error messages.
    Is there a way to import images ?
    Thks