I want to embed a map in a wiki page.

writes the line: The attachment id given is not valid.

attachment is for things like images or videos or other binary data that has been uploaded to a page (or other content). so attachment will not work for maps, which are a form of content.

as for embedding a map in a page - there is not a plugin for this currently. gmap package doesnt have this kind of support built in well yet either. probably would be easy to add, but needs to be written.

Would be nice and simple if all content types could be embedded in a wiki page. For now I've created an image of a map. Clicking it should load the map, but its link is truncated at the equal sign:
becomes
which loads the default map.