Hello,
This discussion is 11 years old, but In order not to open a new discussion on this same topic I will place my question here.
I want to show the poster of an Exhibition as the occurrence (exhibition) media. I think this is a perfect example of the request that originated this discussion: uploading media not intended as object, but as an information element of some other entity.
Since there isn't a Media element in the Occurrence editors screens, I've added a new screen named "Resources" and have selected the element "(Occurrence) Related object representation".

I have created the Exhibition (new occurrence) and added the representation making it accessible to public.

This Exhibition will exhibit a painting of our collection. Accordingly, I have included the media representation of the exhibited object in the occurrence's Relationships.

With this in place (Pawtucket, default theme):
Browsing occurrences looks good:

Clicking on the element goes to /Detail/occurrences, where I would expect to see a larger representation of the Exhibition poster and a small image of the object relationship. However, it is not the case: the occurrence information is correctly displayed, but the represented media is not the occurrence media representation, as I would expect, but the representation of the related object.

What I'm trying to accomplish is a screen similar to the /Detail/archival page I found on the Kress theme, where the occurrence media representation is shown along with the related object.

In this Kress UI, the occurrence media representation is missing, probably because this particular theme may be checking some other database.
Bottom line. I'm trying to understand how this works and how does the default theme deal with occurrence media representations as opposed to how a theme such as Kress does.