Jan,
It is not the easiest or clearest part of the software. Basically you can ignore the top item
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Per the attachment you can ignore the Upper Area of Gallery and simply need to chose Something under User Gallery.
Basically, it is trying to let you add a Picture anywhere, not just to you own Gallery. This ends up in just making it confusing. Let me know if this does not make sense and I would be happy to assist.
mark