On my Intel Mac, every voice preview or audiobook render fails with "Narration engine failed to start". What can I do?

Update to version 1.9.5 or later. Versions before 1.9.5 of the Intel Mac build were missing one native image library that the narration engine loads at startup, so the engine could not start on any Intel Mac, no matter how the app was installed or which security settings were changed. Apple Silicon Macs and Windows were not affected. After updating, open BookyAI Audio and preview a voice: the engine downloads on first use (about 90 MB, one time) and then works normally. Your books, license and settings are unchanged.