For the case we have in the bug report (German translation) we could use this translation: Dokument öffnen (OpenDocument).
By the way, I believe that our original English message should have said "OpenDocument" rather than "Open Document".
As the translation originates from Export formats, do not use 'Dokument öffnen.' This refers only to the action of opening a document, but not to a transliteration of the ODT format. Use 'OpenDocument' w/o spacing.