The documentation (both at the intro text of the “1-click app” and in the linked documentation article) is missing any mention of when/how the actual genealogy data is flowed into the droplet.
There ought to be mention of prepping an export (GEDCOM, .gramps compressed or .gramps XML) file or backup(?) file. Then an explicit statement of which step is where the file is imported/uploaded. Is it in the setup script?