1/ You’re welcome!
2/ Yes, update the theme, and provide temporary wp-admin and FTP access.
Translation files of the theme should be placed in /wp-content/languages/themes/ folder,
plugins, like core plugin, in /wp-content/languages/plugins folder.
After every update, you need to synchronize translation – https://xstore.helpscoutdocs.com/article/103-translation-files-update Sometimes new strings are added, and only after synchronization, you’ll be able to translate new strings or strings that were changed. Not always, but some strings can be missing after the sync and you need to find and translate them one more time, this is independent of us and relates to WP functionality. So Sync translation of the theme and plugins, then try to find and translate mentioned strings.
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.