Quote - Thanks but could you enlighten me a bit? What are binary morph targets used for? I'm not really that far with Poser.

They are a way of reducing the the overall file size required by storing the morph data in a seperate file (with the extension PMD) instead of being in text directly in the scene / character / prop / pose file.

There are other ways to save disk space, compressing the files using Poser's or Window's built-in support.
However most applications that interoperate with Poser don't get along with either binary morphs or Poser's compression, so these have to be turned off.