I partially fixed the image.fodt.slim so that it embeds the image. The hangup I'm having is mixing the @target attribute with some hard coded text in a "Layout" message placed afterwards.

You can see my edit at https://github.com/gregturn/asciidoc-packt/pull/10.

P.S. I created https://github.com/gregturn/asciidoc-packt/blob/master/example.adoc based on your example, to provide a nice showcase of what this backend does, and to also help test outcomes.