Got the installer working. Fixed a few bugs including a nasty-to-debug issue where the lang_id was being hardcoded during installation, resulting in strings being inserted with the wrong lang_id causing an infinfinite loop with fetch() throwing a "no strings" error and using template (which calls fetch()) to complain

{
  // Language metadata
  lang_name_english: 'English',
  lang_name_native: 'English',
  lang_code: 'eng'
}