I'm not sure if I have the "Truck Version" or not, but I do have Primo 2.4 (405512) and it definitely works with TTS. In fact, you can use both Loquendo and Nuance TTS voices with it - at the same time. By reviewing logs, I found that it will actually unload one TTS driver and load the other one as you switch between the different type of voice files (originally, I had worried that they were both in RAM at the same time).
So if he's using the same 405512 that I am, he can use Loquendo and/or Nuance TTS voices.
I have a feeling that he doesn't have the proper Nuance TTS files in the tts_nua_v5 directory (for the specific voices he's trying to use). That's just a hunch though!
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