Re: picture attachments.
I generally save them to a folder as *.PNG format, then use the Attach Files feature in the Additional Options pane.
You'll have to browse to each picture, then Upload, then Close that dialog window.
In general if you're logged in as a user, attached files that are pictures will show up without you having to also add them to your post.
When you're not logged in as a user, or if the file is a ZIP file, you have to click on the attached file link to download or open it.
I think that this forum uses a different markup language than Reddit or Imgur, so direct links to Imgur just open that album, rather than showing the picture inline.