Even if you force-install 5.6.6 on macOS Monterey or Ventura using hacks, expect:
Because this version is no longer actively distributed on the main Native Instruments download pages, many third-party links lead to cracked software, peer-to-peer torrents, or malicious sites. Downloading installers from unverified sources exposes your Mac to keyloggers, adware, and ransomware. DAW Instability kontakt 5.6.6 mac