Original plugin zip files normally have the plugin slug as base path inside the zip file (“download-plugin/” in case of this plugin itself). When I download a zip with this plugin, the resulting zip file lacks that folder in the files’ paths.
When uploading such a zip file to a WordPress installation, the result is the same as when uploading the original zip file (WordPress seems to handle that automatically). When extracting locally into the file system, I end up with a different folder structure compared to when extracitng original plugin files.